СИСТЕМА С ИНТЕРФЕРОМЕТРАМИ

Изобретение относится к области интерферометрии. Система с интерферометрами содержит содержит волоконно-оптический датчик, который может иметь часть датчика Майкельсона и часть датчика Маха-Цендера. Первый разветвитель-объединитель может быть сконфигурирован для разделения света между первой оптоволоконной частью и второй оптоволоконной частью. Первое устройство сопряжения поляризации фаз может быть сконфигурировано для сопряжения фазы поляризации падающего света, соответствующего первой оптоволоконной части, и второе устройство сопряжения фазы поляризации может быть сконфигурировано для сопряжения фазы поляризации падающего света, соответствующего второй оптоволоконной части. Каждое, первое и второе устройства сопряжения поляризации фаз могут быть сконфигурированы для отражения света в детектор и через соответствующие первую и вторую оптоволоконные части. Объединитель может быть сконфигурирован для объединения света в первой оптоволоконной части со светом во второй оптоволоконной части ...

СИСТЕМА И СПОСОБ ДЛЯ ИЗМЕРЕНИЯ ВНУТРЕННИХ РАЗМЕРОВ ОБЪЕКТА С ИСПОЛЬЗОВАНИЕМ ОПТИЧЕСКОЙ КОГЕРЕНТНОЙ ТОМОГРАФИИ

Группа изобретений относится к медицине. Система для оптического измерения, посредством оптической когерентной томографии (ОКТ), внутренних размеров обследуемого объекта, содержащего глаз, при этом объект имеет внутренние границы раздела, на которых изменяется показатель преломления, а система, выполненная с возможностью детектирования части падающего излучения, отраженной и/или рассеянной указанными границами в обратном направлении. Система содержит: первое ОКТ-устройство (ОКТ1), выполненное с возможностью измерять внутренние размеры в первом объеме, представляющем собой часть объекта, и второе ОКТ-устройство (ОКТ2), выполненное с возможностью измерять внутренние размеры во втором объеме, представляющем собой часть того же объекта, причем указанный второй объем отличается от первого объема. ОКТ1 выполнено с возможностью испускать первый пучок (В1) первого излучения и имеет первое продольное разрешение (Δz1∞(λ1)/Δλ1), задаваемое длинами волн первого излучения, находящимися в первом интервале ...

Интерферометр для измерения линейных перемещений

Интерферометр для измерения линейных перемещений относится к области измерительной техники и может быть использован для измерения линейных перемещений движущихся объектов, например, подвижных частей прецизионных станков. Изобретение направлено на повышение функциональной возможности оптического интерферометра без уменьшения точности измерения за счет разделения конструкции, состоящей из двух уголковых отражателей, и использования данной конструкции не только для измерения отклонений от прямолинейности, но и для измерения линейных перемещений подвижных объектов. Это достигается тем, что в конструкции интерферометра для измерения отклонений от прямолинейности конструкцию, состоящую из двух уголковых отражателей, разделяют таким образом, что один из уголковых отражателей остается неподвижным, а по движению второго уголкового отражателя судят о перемещении подвижного объекта. 1 ил.

УСТРОЙСТВО КОНТРОЛЯ АДДИТИВНОГО ИЗГОТОВЛЕНИЯ ДЕТАЛЕЙ

Полезная модель относится к области аддитивного формирования изделий, а именно к устройствам контроля 3D-печати на основе голографических, интерферометрических измерений, структурированного света, а также фотограмметрии, и может быть использована для получения информации о форме объекта, его деформации, наличии внутренних подповерхностных дефектов заготовки и напряженных состояниях материала. Устройство контроля аддитивного изготовления детали содержит соединенные между собой осветительный блок в виде источника когерентного излучения с линзой, интерференционный блок и вычислительный блок. Интерференционный блок выполнен на основе интерферометра сдвига, содержащего наклонное и перемещаемое вдоль оптической оси зеркала. Вычислительный блок выполнен с возможностью расшифровки интерферограмм методом фазовых шагов и вычисления текущих значений внутренних напряжений в детали. Полезная модель позволяет повысить качество изготавливаемых деталей. 3 ил.

ИНФРАКРАСНЫЙ ИНТЕРФЕРОМЕТР

Полезная модель относится к области измерительной техники и касается инфракрасного интерферометра. Интерферометр включает в себя: ИК лазер, расширитель, светоделитель в виде оптического клина, опорную и рабочую ветви. Опорная ветвь содержит компенсатор разности хода с линейной направляющей, кареткой и эталонным плоским зеркалом с двухкоординатной угловой подвижкой. Рабочая ветвь содержит эталонный объектив, проекционную систему и матричный ИК фотоприемник, подключенный к ЭВМ. Эталонное плоское зеркало с помощью двухкоординатной угловой подвижки установлено перпендикулярно оптической оси и имеет возможность линейного осевого и углового перемещений на пьезоприводе, подключенном к блоку управления, связанному с ЭВМ. Технический результат заключается в расширении функциональных возможностей и повышении точности измерений.1 ил.

УСТРОЙСТВО ИЗМЕРЕНИЯ ЗАДЕРЖКИ РАСПРОСТРАНЕНИЯ ОПТИЧЕСКОГО СИГНАЛА В СРЕДЕ

Изобретение относится к области измерительной техники и касается устройства измерения задержки распространения оптического сигнала в среде. Устройство включает в себя два фемтосекундных инфракрасных лазера, интерферометр Майкельсона с известным опорным плечом и измерительным плечом - измеряемой линией, фотодетектор, принимающий сигнал с измеряемой линии, и регистратор. Оба лазера являются сверхширокополосными, различаются периодом повторения импульсов и установлены с возможностью поочередного подключения в схему устройства через два последовательно соединенных волоконных затвора, обеспечивающих формирование воздействующего сигнала для пропуска через тестируемую волоконную линию. В качестве фотодетектора используют высокочастотный фотодетектор, а в качестве регистратора - широкополосный осциллограф с программным обеспечением, позволяющим проводить корреляционный анализ двух групп значений. Технический результат заключается в повышении точности измерений задержки распространения оптического ...

Устройство для контроля торических поверхностей оптических деталей

Полезная модель относится к области технологии обработки оптических деталей и может быть использована для контроля торических поверхностей преимущественно крупногабаритных оптических деталей. Устройство для контроля торических поверхностей оптических деталей, содержащее источник излучения - лазер, излучение которого падает на контролируемую поверхность детали, закрепленной на юстировочном столе, оптическую систему для формирования сферического волнового фронта, расположенную в переднем фокусе контролируемой поверхности и состоящую из объектива, и расположенный в заднем фокусе контролируемой поверхности оптический блок для анализа волнового фронта, в оптическую систему которого входят светоделитель, эталонное зеркало и наблюдательная система–анализатор. При этом устройство снабжено дополнительно светоделительной пластиной, установленной между источником излучения - лазером и оптической системой для формирования сферического волнового фронта так, что отраженное от ее поверхности лазерное ...

СПОСОБ ИЗМЕРЕНИЯ ФОРМЫ ВНЕОСЕВОЙ АСФЕРИЧЕСКОЙ ОПТИЧЕСКОЙ ДЕТАЛИ

Изобретение предназначено для контроля формы выпуклых асферических поверхностей внеосевых зеркал телескопов в процессе их формообразования. Способ осуществляют с использованием интерферометра и корректора волнового фронта в виде круглого дифракционного оптического элемента (ДОЭ) диаметром, большим габарита оптической детали. ДОЭ состоит из оптической подложки, на поверхности которой нанесены основная дифракционная пропускающая структура и дополнительные отражающие дифракционные структуры - центрирующие в виде центрального круга вокруг оси ДОЭ и четырех элементов в виде отрезков кольца по окружности ДОЭ, расположенных диаметрально противоположно, а также с четырьмя фокусирующими элементами, расположенными по окружности ДОЭ диаметрально противоположно между четырех центрирующих элементов. ДОЭ устанавливают в зоне охвата внеосевой поверхности, настраивают его с помощью дополнительных структур относительно интерферометра и вместе с интерферометром - относительно контролируемой поверхности.

ИНТЕРФЕРОМЕТР С ФУНКЦИЕЙ ДИФФЕРЕНЦИАЛЬНЫХ ИЗМЕРЕНИЙ

Изобретение относится к области измерительной техники. Интерферометр с функцией дифференциальных измерений содержит лазер, расширитель, светоделитель в виде оптического клина, размещенные по ходу луча в опорной ветви эталонное плоское зеркало с угловыми ортогональными подвижками и линейным осевым пьезоприводом, подключенным к ЭВМ через блок управления, размещенный в рабочей ветви эталонный объектив, проекционную систему и матричный фотоприемник, подключенный к ЭВМ, при этом эталонное плоское зеркало с линейным пьезоприводом дополнительно размещено на угловом пьезоприводе, подключенном к ЭВМ через блок управления, а перед эталонным объективом в рабочей ветви установлены сменные компенсаторы сферической аберрации. Технический результат - расширение функциональных возможностей интерферометра путем обеспечения работы в нескольких режимах: амплитудном, фазовом и муаровом при увеличении диапазона измерения дифференциальных аберраций оптических поверхностей и увеличении точности работы в амплитудном ...

Способ демодуляции сигнала волоконно-оптического датчика тока

Изобретение относится к области оптических способов измерения физических величин с использованием фазовых волоконно-оптических датчиков, в том числе волоконно-оптических интерферометров, применяемых для измерения электромагнитных полей. Техническим результатом является повышение точности демодуляции сигнала волоконно-оптического датчика тока при непостоянстве амплитуды вспомогательной модуляции разности фаз, осуществляемой в фазовом волоконно-оптическом датчике гармоническим сигналом. Способ демодуляции сигнала волоконно-оптического датчика тока включает вспомогательную модуляцию разности фаз в фазовом волоконно-оптическом датчике гармоническим сигналом, выделение из сигнала, получаемого с фотоприемника, установленного на выходе фазового волоконно-оптического датчика, напряжений первой и второй гармоник частоты вспомогательной модуляции, синхронное детектирование напряжений первой и второй гармоник частоты вспомогательной модуляции и вычисление искомой разности фаз. При этом выделяют напряжение ...

Оптический смеситель излучения с применением призм из оптически активных материалов

Изобретение предназначено для получения сигналов вращения четырехчастотного лазерного гироскопа. Оптический смеситель лучей, распространяющихся во встречных направлениях в резонаторе четырехчастотного лазерного гироскопа, предназначен для одновременного детектирования интерференционных картин, независимо полученных для излучения левой и правой круговых поляризаций. Смеситель включает сводящий встречные лучи элемент, два направляющих глухих зеркала и один или два анизотропных элемента, состоящих из двух призм из левого и одной призмы из правого кристаллов оптически активного материала, обеспечивающих разведение по углу и координате лучей различных круговых поляризаций. Смеситель может содержать один анизотропный элемент, при этом в качестве сводящего встречные лучи элемента может быть использована треугольная призма, а на отражающие поверхности глухих зеркал нанесены полуволновые фазовые пластины. Смеситель может содержать два анизотропных элемента, а в качестве сводящего встречные лучи ...

Волоконно-оптическая измерительная система

Изобретение относится к области волоконной оптики и касается способа регистрации параметров, получаемых с датчиков, основанных на волоконных Брэгговских решетках (ВБР). Заявленная волоконно-оптическая измерительная система включает широкополосный источник излучения (1), первый оптический разветвитель (2), с по меньшей мере двумя оптоволоконными выходами, по меньшей мере один циркулятор (3), содержащий по меньшей мере один оптоволоконный выход для подключения ВБР-датчиков (4), первый фотоприемник (5) и блок управления и обработки (6). При этом выход широкополосного источника излучения (1) соединен с первым оптическим разветвителем (2), один из выходов которого соединен с входом циркулятора (3), прямой выход которого соединен с волоконно-оптическими датчиками (4), а обратный выход - с приемным трактом, с помощью которого происходит селекция по длине волны отраженного сигнала, и подключенным к первому фотоприемнику (5), который, в свою очередь, подключен к блоку управления и обработки (6).

ОПТИЧЕСКИЙ КОГЕРЕНТНЫЙ ТОМОГРАФ С ЗАКОДИРОВАННЫМ В ДИСПЕРСИИ ШИРОКИМ ДИАПАЗОНОМ

СИСТЕМА УЛЬТРАЗВУКОВОГО КОНТРОЛЯ

... 1. Система ультразвукового контроля объекта, содержащая по меньшей мере один передающий блок и множество приемных блоков,причем каждый приемный блок оптически измеряет колебание поверхности объекта;при этом система содержит осветительный лазер, свет которого освещает поверхность в зоне измерения,приемный блок выполнен с возможностью принимать свет, падающий на него из зоны измерения;каждому приемному блоку соответствует одна зона измерения, так что приемный блок принимает свет, падающий на него из зоны измерения;световодная система излучает свет лазера в своем первом положении в первую зону измерения, а во втором положении - во вторую зону измерения;световодная система делит свет лазера и излучает его в одну и другую зоны измерения;отличающаяся тем, что содержит множество передающих блоков, при этом каждый передающий блок создает искровой промежуток, причем искровой промежуток создает на поверхности и/или в объекте ультразвуковое колебание.2. Система по п.1, отличающаяся тем, что передающий ...

Сканирующий интерферометр Фабри-Перо на основе ИТ-28-30

Изобретение относится к оптике, к оптическим устройствам, основанным на использовании явлений интерференции световых потоков, например, в интерферометрах Фабри-Перо, применяемых в научных исследованиях и технике для сканирования спектра при спектральном анализе оптического излучения с высокой разрешающей способностью или модуляции света, а также в перестраиваемых по длине волны лазерах. Техническим результатом изобретения является создание устройства, в котором минимизирована тепловая нестабильность интерферометра, выполнено расширение базы интерферометра до 30 мм и уменьшена расстройка параллельности зеркал. Указанный технический результат достигается в сканирующем интерферометре Фабри-Перо на основе ИТ-28-30, включающем: два плоскопараллельных зеркала, где рабочие плоскости установлены одно к другому и опираются на базу из инвара из стандартного набора ИТ-28-30, причем подвижное зеркало установлено в обойме упругой диафрагмы, а неподвижное в обойме предварительной подстройки; стандартный ...

Устройство для измерения радиуса оптической сферической поверхности

Использование: в измерительной технике, для измерения радиуса оптических сферических поверхностей, а также при контроле оптических деталей как в процессе их изготовления, так и после него. В устройство введен дополнительный светоделительный элемент, установленный между когерентным источником света и светоделительным элементом интерферометра Физо, кроме того, устройство дополнено некогерентным осветителем с регулируемым сдвигом фаз, включающим некогерентный источник света, светоделительный элемент некогерентного осветителя с регулируемым сдвигом фаз, подвижное и неподвижное зеркала, линейный энкодер подвижного зеркала некогерентного осветителя с регулируемым сдвигом фаз, фокусирующую линзу, при этом некогерентный осветитель с регулируемым сдвигом фаз связан с дополнительным светоделительным элементом таким образом, что расходящийся пучок света от него падает на дополнительный светоделительный элемент. Технический результат заключается в расширении функциональных возможностей устройства, ...

Element with varying length

The length varying element is provided in an apparatus which determines, varies and/or measures the position and/or orientation of a reference object in a space using a predetermined number of such elements. Each length varying element has at an end a hinge defining at least approximately a deflection point. Each element also has a part whose length varies. A measurement scale system measures the length and/or change in length of the length varying element. At least one measurement scale system is arranged outside drive, guide and/or support structures of the length varying element and is arranged at least partly symmetrical to a connection line of the element lying between the deflection points.

Verfahren zur Erhoehung der Empfindlichkeit von Drehspulinstrumenten

Formbestimmungsvorrichtung

Eine Aufgabe der vorliegenden Erfindung besteht darin, eine Dickenverteilung präzise unter Verwendung eines einfachen Vorrichtungsaufbaus ohne Beeinträchtigung durch Schwingungen eines zu messenden Objektes zu messen. Bei der vorliegenden Erfindung wird für jede von den vorderen und den hinteren Oberflächen eines zu messenden Objektes 1 jeder der Lichtstrahlen aus dem Erhalt durch ein in zwei Strahlen erfolgendes Zerlegen eines emittierten Lichtstrahles aus einer Laserlichtquelle 2 weiter in zwei Strahlen zerlegt. Sodann werden die Lichtstrahlen an Bezugsoberflächen und Messpunkten 1a und 1b wechselseitig in einer vorderen und hinteren Beziehung reflektiert, sodass Nichtinterferenzlichtstrahlen Pax und Pbx aufgenommen werden, von denen jeder den Bezugslichtstrahl und den Objektlichtstrahl als wechselseitig orthogonale Polarisationskomponenten enthält. Sodann wird jeder Lichtstrahl in eine Mehrzahl zerlegt. An einem oder mehreren der zerlegten Lichtstrahlen wird eine Phasenverschiebung vorgenommen ...

Interferometer

Verfahren und Anordnung zur Abfrage von faseroptischen interferometrischen Fühlern in Vielkanalanwendungen

Fabry-Perot-Interferometer

Verfahren und Vorrichtung zum Fertigstellen von Linsen mittels eines Interferometers

Interferenzlichtmodulator

Optical sensor and method of use

An interferometer apparatus for an optical fibre system and method of use is described. The interferometer comprises an optical coupler and optical fibres which define first and second optical paths. Light propagating in the first and second optical paths is refelected back to the optical coupler to generate an interference signal. First, second and third interference signal components are directed towards respective first, second and third photodetectors. The third photodetector is connected to the coupler via a non-reciprocal optical device and is configured to measure the intensity of the third interference signal component directed back towards the input fibre. Methods of use in applications to monitoring acoustic perturbations and a calibration method are described.

Optical sensor and method of use

An interferometer apparatus for an optical fibre sensing system, the apparatus comprising an optical coupler with first and second ports connected to first and second optical paths which have a path length difference that defines a spatial resolution of the system and where a third coupler port receives an input from an optical source and further comprises first, second and third photodetectors coupled to the respective ports. Preferably an optical circulator is coupled to the third coupler port and there may be an optical amplifier and filter configured to filter out Amplified Spontaneous Emission noise. Preferable is the introduction of third and fourth optical paths with a plurality of optical switches arranged to change and/or select different combinations of the paths to provide multi-spatial resolution. Also an interferometer system comprising a plurality of interferometer apparatus 602-605 arranged in series or parallel or a combination of both, where the interferometers may have ...

Compact high resolution imaging apparatus

Method and apparatus for optical sensing

Method and apparatus for optical sensing

Method and apparatus for optical sensing

White light interferometer

Integrated interferometer

Construction of a fabry perot interferometer (etalon)

... 312,534. Williams, W. E. July 11, 1928. Interferometers.-Optical interferometers of the reflection echelon or the Fabry Perot etalon type have the separation between successive reflecting surfaces maintained substantially constant by making the plates (in the one type) or the spacing means (in the other type) of fused silica or other material having a negligible coefficient of thermal expansion, the contacting surfaces being in optical contact. The echelon plates 1 are optical worked until plane parallel to a high degree of accuracy and are placed in optical contact, being but lightly held in a clamp comprising end plates 2 and rods 3 with nuts 4. The rods are of invar steel and the thickness of the washers 5 is chosen so that the resulting thermal expansion is the same as that of thet plates. The steps 6 are metallized by cathodic deposition. The two plates, 13, 14, Fig. 2, of the Fabry Perot interferometer are, spaced apart by three blocks 15 located at equal radial angles round the plates ...

Mach-Zehnder Interferometers

A Mach-Zehnder interferometer 200 comprising an optical splitter 201 having at least one input 203R and at least two outputs 204L . 2048, an optical recombiner 202 having at least two inputs 205L .205R and at least one output 2068 and a pair of interferometer arms 207L 2078. Each of the arms couples an output of the splitter to an input of the recombiner. The arms are configured such that each of the outputs of the splitter is coupled to an opposite side input of the recombiner so as to compensate for phase imbalance of light propagating through the arms. The interferometer is configured such that the splitter and the recombiner operate in cross-state to compensate for split ratio offset errors in the splitter and recombiner.

Rheometer with optical interferometer

Method of flow monitoring

Light source apparatus for photo-diagnosis and phototherapy

Laser interferometer mirror assembly

Optical sensor

Laser length measuring device

Optical instruments of the interference type

INTERFEROMETER THICKNESS GAUGE

... 1337273 Interferometer thickness gauge TRADE & INDUSTRY SECRETARY OF STATE FOR 19 April 1971 [9 Feb 1970] 6181/70 Heading G1A In a device, for measuring the thickness of strip of steel 1 moving over and in close contact with a roller 3, wide band infrared light from a mercury vapour lamp 7 is directed by a beam divider 9 (formed of polyethylene-terephthalate) along two paths as shown to be reflected off the roller 3 and the strip 1 and subsequently recombined by the divider 9 and passed to a golaycell 13, the two path lengths being equalised by moving a mirror 11 until all the radiation reaching the detector is in phase. The position of the mirror in the "in-phase" position provides a measure of the strip thickness. The mirror 11 is oscillated in a direction normal to its plane surface by a translator/transducer unit 14. An output from the translator/transducer unit is fed to an X input of an X-Y recorder 16 and the golay-cell output is fed to the Y input of the recorder 16 to produce a ...

Coherent radiation detection and ranging device

Apparatus for detecting and/or measuring the range of a coherent radiation source. The apparatus measures range by measuring wavefront curvature and is particularly for use at long ranges where the change in curvature with range is very small. An afocal telescope 2 receives radiation 1 and supplies a beam 3 having a curvature which is range dependent. This is divided into two beams 5, 6 in a shearing interferometer, one beam being converted to a plane wave by adjustable focus lens system 10 under the control of detector 15. The two component beams 5, 6 are recombined at plate 4 to form an interference pattern detected at 19 to provide a range measurement.

The ophthalmologic measuring length using double beam space-time domain short coherence interferometry autotuning wavelength locker

Diese Anmeldung betrifft die Messung intraokulärer Längen durch Doppelstrahl Fourier-Kurzkohärenz-Interferometrie basierend auf Fresnel-Zonen-artigen Raum-Zeit-Domäne Interferogrammen (RZI) der Purkinje-Sanson Reflexe. Das Messobjekt Auge (1) wird von einem Bündel zueinander paralleler gleichfrequenter monochromatischer Doppelstrahlen (11) mit in zeitlicher Sequenz unterschiedlichen Wellenlängen beleuchtet. Die Wellenlängen-Spektren der Raum-Zeit-Domäne Interferogramme (51) werden von einem Photodetektor-Array (70) mit vorgeschaltetem Bildverstärker (BV) oder einer Digitalkamera verstärkt und von einem Photodetektor-Array(70) registriert. Hierbei werden Blickrichtung und Position des Probandenauges mit optischen Hilfsmitteln fixiert und mittels akustischer und optischer Hilfsmittel kontrolliert. Eine Zoom-Optik (52) im Ausgangsstrahl des ophthalmologischen Interferometers erlaubt - als inverse Lupe fungierend - durch einfaches Fokussieren die virtuellen Fresnel-Zonen-artigen Raum-Zeit-Domäne ...

Mechanism for the reduction of an entrance pulse rate

Spectrometric instrument

Abstract Spectrometric Instrument A spectrometric instrument (38) comprising: a scanning interferometer (40,42,44) having a beamsplitter (40) for dividing incident optical radiation into a reflected beam, following a reflected beam path and a transmitted beam following a transmitted beam path; a monochromatic optical radiation source (52) for launching a reference beam into the interferometer (40,42,44) along a first propagation path (62) to be initially incident on a first face (40') of the beamsplitter (40); an observation optical radiation source (46) for launching a divergent observation beam (64) into the interferometer (4,6,8) along a second propagation path (66) to be initially incident on the first face (40') of beamsplitter (40) and overlap the reference beam at the first face (40'); wherein the radiation sources (52;46) cooperate to generate a first angle (0) between the directions of propagation of the two beams along respective first (62) and second (66) propagation paths when ...

Optical coherence tomography technique

A technique for optical coherence tomography is provided. As to a device aspect of the technique, a device (100b) comprises a light generator (110), a dispersive medium (120), an optical coupler (130) and a detector (140). The light generator is adapted to generate a series of input pulses (202, 204, 206) of coherent light, each input pulse of the series having an input pulse width ( ...

Movable wide-angle ophthalmic surgical system

A surgical imaging system can include at least one light source, configured to generate a light beam; a beam guidance system, configured to guide the light beam from the light source; a beam scanner, configured to receive the light from the beam guidance system, and to generate a scanned light beam; a beam coupler, configured to redirect the scanned light beam; and a wide field of view (WFOV) lens, configured to guide the redirected scanned light beam into a target region of a procedure eye; wherein the beam coupler is movably positioned relative to the procedure eye such that the beam coupler is selectively movable to change at least one of an incidence angle of the redirected scanned light beam into the procedure eye and the target region of the procedure eye.

Optical tomography apparatus and method

The invention relates to an optical tomography apparatus which comprises: a polychromatic light source (SLM), a one-dimensional optical sensor (CIM), an interferometric microscope (Ml), a one-dimensional confocal spatial filtering system (FS), an actuator system (PR, TR1, TR2, TR3) making it possible to perform a unidirectional depthwise scan of an object to be observed and a processor (PR) for reconstructing a two-dimensional image of a section of said object from a plurality of one-dimensional interferential images acquired by said image sensor during said one-directional scan. The invention further relates to an optical tomography method using such an apparatus.

Caching of intra-layer calculations for rapid rigorous coupled-wave analyses

METHOD FOR SPECKLE MITIGATION IN AN INTERFEROMETRIC DISTANCE METER AND CORRESPONDING DISTANCE METER

A method for speckle mitigation in an interferometric distance meter comprises the steps of transmitting optical radiation (12) with at least one wavelength to a target (11) to be surveyed, receiving a portion of the optical radiation (12) scattered back by the target (11) in an optical axis (OA), wherein the optical radiation (12) forms a speckle field, converting the received optical radiation (12) into at least one received signal, determining a true distance to the target (11) from the received signal by absolute or incremental interferometric distance measurements. In the method the true pointing direction relative to the optical axis (OA) is determined, wherein the distance error due to speckle effects is corrected.

OPTICAL SENSOR AND METHOD OF USE

An interferometer apparatus for an optical fibre system and method of use is described. The interferometer comprises an optical coupler and optical fibres which define first and second optical paths. Light propagating in the first and second optical paths is refelected back to the optical coupler to generate an interference signal. First, second and third interference signal components are directed towards respective first, second and third photodetectors. The third photodetector is connected to the coupler via a non-reciprocal optical device and is configured to measure the intensity of the third interference signal component directed back towards the input fibre. Methods of use in applications to monitoring acoustic perturbations and a calibration method are described.

SOIL COMPACTION METHOD USING A LASER SCANNER

L'invention concerne un procédé de compactage d'un sol, dans lequel : a) on réalise plusieurs fois un cycle de pilonnage d'une zone d'impact du sol au cours de laquelle : on laisse tomber une masse (16) sur la zone d'impact depuis une hauteur prédéterminée (A); et après l'impact de la masse (16) sur la zone d'impact, on acquiert un nuage de points à l'aide d'un scanner laser afin d'obtenir une image radar d'au moins l'empreinte (E) de la masse dans le sol; b) on détermine au moins une donnée caractéristique du compactage du sol à partir d'au moins une des images radar obtenues à l'issue des cycles de pilonnage.

MINIATURIZED MOBILE, LOW COST OPTICAL COHERENCE TOMOGRAPHY SYSTEM FOR HOME BASED OPHTHALMIC APPLICATIONS

Improved optical coherence tomography systems and methods to measure thickness of the retina are presented. The systems may be compact, handheld, provide in-home monitoring, allow the patient to measure himself or herself, and be robust enough to be dropped while still measuring the retina reliably.

INTERFEROMETRY TESTING OF LENSES, AND SYSTEMS AND DEVICES FOR SAME

Modified MZ (Mach-Zender) interferometers preferably are utilized to analyze the transmitted, aspherical wavefront of an ophthalmic lens by mounting the lens in a cuvette having a rotatable carousel that can hold multiple lenses. Fresh, temperature controlled, saline solution is circulated about the lenses, and the cuvette is positioned in a vertical test arm of the interferometer configuration. Reverse raytracing preferably is utilized to remove aberrations induced into the wavefront as it is imaged from immediately behind the lens to the detector of the interferometer.

METHOD AND APPARATUS FOR ULTRASONIC LASER TESTING

The present invention for detecting ultrasonic displacements includes a detection laser (320) to generate a first pulsed laser beam to generate the ultrasonic surface displacement on a surface of the target (150). A second pulsed laser beam to detect the ultrasonic surface displacement on a surface of the target (ISO). Collection optics to collect phase modulated light from the first pulsed laser beam either reflected or scattered (131) by the target (150). An interferometer which processes the phase modulated light and generate at least one output signal. A processor that processes the at least one output signal to obtain data representative of the ultrasonic surface displacements at the target (150).

WAVEFRONT ANALYSIS METHOD INVOLVING MULTILATERAL INTERFEROMETRY WITH FREQUENCY DIFFERENCE

Le procédé consiste à placer un réseau de diffraction GR à maillage bidimensionnel sur le trajet du faisceau à analyser et à traiter au moins deux interférogrammes à au moins deux couleurs différentes, chaque interférogramme étant obtenu dans un plan Psà partir de deux sous- faisceaux Rl, R2 d'ordres de diffraction différents. Application à l'analyse et à la correction de surfaces d'onde morcelées S.

METHOD AND SYSTEM FOR DETERMINING THE POSITION AND ALIGNMENT OF A SURFACE OF AN OBJECT IN RELATION TO A LASER BEAM

... ²²²The present invention generally relates to a method and system for determining ²the position and alignment of a plane in relation to an intersecting axis and ²using that known position and alignment to allow for corrections to be made ²when using the plane as a reference plane. More particularly, the invention ²relates to a method and system for determining the angle of tilt of a planar ²surface in relation to a laser beam, and using the determined angle of tilt to ²calculate a correction factor to be applied to the laser beam. Briefly stated, ²the method and system ultimately calculates a correction factor, z-offset, ²that is applied when using the laser beam in a procedure.² ...

METHOD AND APPARATUS FOR OPTICAL SENSING

The present invention provides novel apparatus and methods for fast quantitative measurement of perturbation of optical fields transmitted, reflected and or scattered along a length of an optical fibre. The present invention can be used for point sensors as well as distributed sensors or the combination of both. In particular this technique can be applied to distributed sensors while extending dramatically the speed and sensitivity to allow the detection of acoustic perturbations anywhere along a length of an optical fibre while achieving fine spatial resolution. The present invention offers unique advantages in a broad range of acoustic sensing and imaging applications. Typical uses are for monitoring oil and gas wells such as for distributed flow metering and or imaging, seismic imaging, monitoring long cables and pipelines, imaging within large vessels as well as for security applications.

SYSTEM AND METHOD FOR MEASURING INTERNAL DIMENSIONS OF AN OBJECT BY OPTICAL COHERENCE TOMOGRAPHY

A system is provided for optically measuring internal dimensions of a sample object, for example an eye, said object comprising internal interfaces at which the refraction index changes so that a portion of incident light is backreflected and/or backscattered and can be detected, by means of optical coherence tomography, comprising at least one first OCT device adapted to measure internal dimensions in a first partial volume of the object, characterized by a combination with at least one second OCT device adapted to measure internal dimensions in a second partial volume of the same object, wherein the second partial volume is at least partially different from the first partial volume. The first and second OCT devices may share at least partially spatially superimposed first and second sample arms, which may have respective different focal lengths and pass through a common optical lens system toward the object, and which may share a common light source. Internal dimensions in a first partial ...

APPARATUS AND METHOD FOR IDENTIFYING ONE OR MORE AMYLOID BETA PLAQUES IN A PLURALITY OF DISCRETE OCT RETINAL LAYERS

The present invention is an apparatus to produce an OCT of an eye or a brain of a patient to identify one or more plaques in a plurality of discrete OCT retinal layers. The present invention also includes a plurality of methods for identifying one or more plaques in a plurality of discrete OCT retinal layers that can include a contrast agent and a normative database.

SYSTEMS AND METHODS FOR OPTICALLY GENERATED TRIGGER MULTIPLICATION

Systems and methods for providing trigger signals in an optical interrogator, wherein multiple triggers are generated within each period of a varying reference signal, and wherein the triggers are evenly spaced according to the wavenumber of the reference signal. In one embodiment, an optical frequency domain reflectometry system provides a laser beam to a reference interferometer to produce a reference signal. This signal is passed through a 4x4 optical coupler which splits the signal Into a first signal and a second signal that is 90 degrees out of phase with the first signal. These signals are converted to electrical signals, and a trigger unit generates triggers at points at which the two electrical signals have zero-crossings, and at which the magnitudes of the signals are equal. The resulting triggers remain evenly spaced within the period of the reference signals, even when the period is changed.

OCT SYSTEM WITH PHASE SENSITIVE INTERFERENCE SIGNAL SAMPLING

An OCT system and particularly its clock system generates a k-clock signal but also generates an optical frequency reference sweep signal that, for example, indicates the start of the sweep or an absolute frequency reference associated with the sweep at least for the purposes of sampling of the interference signal and/or processing of that interference signal into the OCT images. This optical frequency reference sweep signal is generated at exactly the same frequency of the swept optical signal from sweep to sweep of that signal. This ensures that the sampling of the interference signal occurs at the same frequencies, sweep to sweep.

Verfahren und Vorrichtung zur Bestimmung des örtlichen Verlaufes des Brechungsindexes eines in einer Zelle befindlichen Mediums.

Interferometer

Interféromètre à polarisation

Interferometer

Elektrooptische Einrichtung

Appareil optique de contrôle et de mesure.

Interféromètre comportant une surface séparatrice semi-réfléchissante.

Appareil pour la mesure de très petites longueurs.

Interferometer zu Messzwecken

Vorrichtung zur Längenmessung

Interferenzkomparator

Two beam interferrometer length measuring instrument - has no first order tilting error and includes beam splitter and adjustable reflector

The instrument comprises a light source (1), a beam splitter, a fixed reflector (3) and an adjustable reflector (8) in the form of a triple mirror. The fixed reflector produces measuring and reference beams and is also a triple mirror with two partially transmitting mirrors as dividing elements. The first and/or second reflection has a central aperture in which the test piece is located coaxial with the mirrors. Both reflectors are connected to viewers (9) and are independently adjustable relative to the test piece. The reflectors are symmetrically arranged on either side of the central axis.

Laser-Verschiebungsmesser

Vorrichtung zur interferentiellen Messwertbildung für Mess- und Steuereinrichtungen und Verfahren zum Betrieb der Vorrichtung

Interferenzkomparator

Interferometer

Verfahren und Einrichtung zur angenähert proportionalen Untersetzung von Impulsreihen

Interferometer

Interféromètre à différence de marche variable

Interferometer

Interferometrisches Längenmessgerät

Interferometer for precision length measurement

Interferometer for precision length measurement comprises laser, two beam deflectors, feeler, photodetector and electronics ...

Method for interferometric testing of a virtually right angle between two optical surfaces, and device for carrying it out

For the purpose of testing the dimensional accuracy of right angles (3) between optical surfaces (1, 2), a coherent collimated light bundle (5) is irradiated centrally and perpendicular to the angle edge (4) into the angle (3) and onto the two surfaces (1, 2) of the object via a transparent plane plate (8). Parts of the light bundle (5) are deflected and superimposed by the plane plate (8) after reflection at the object (1, 2), a non-localised interference field being produced. An error of the angle (3) is expressed in a component of the interference fringes in the field which alters their angular position. Defocusing the incident collimated light bundle (5) achieves elimination of the error component, and thus a specific desired angular position of the interference fringes in the field, the magnitude of the defocusing at the objective of a beam-expanding telescope (7) that is required for the error compensation directly specifying the error of the angle (3) to be tested. This shearing ...

Procedure and device for the range finding.

OCT-Vorrichtung und Verfahren zum Durchführen einer OCT-Messung.

Die Erfindung betrifft eine OCT-Vorrichtung, umfassend eine OCT-Lichtquelle (15), eine OCT-Auswerteeinheit (16), einen ersten OCT-Lichtleiter (19), einen zweiten OCT-Lichtleiter (20) und ein Umschaltmodul (18). Das Licht von der OCT-Lichtquelle (15) tritt durch das Umschaltmodul (18) hindurch. In einem ersten Zustand des Umschaltmoduls (18) wird das OCT-Licht zu einem Eintrittsende des ersten OCT-Lichtleiters (19) geleitet. In einem zweiten Zustand des Umschaltmoduls (18) wird das OCT-Licht zu einem Eintrittsende des zweiten OCT-Lichtleiters (20) geleitet. Zwischen dem Umschaltmodul (18) und der Objektebene ist eine dem ersten OCT-Lichtleiter (19) zugeordnete Scaneinrichtung (29) angeordnet. Die Objektebene ist dadurch gekennzeichnet, dass der OCT-Strahlengang in einem Betriebszustand der OCT-Vorrichtung in der Objektebene fokussiert ist. Die erfindungsgemäße OCT-Vorrichtung kann flexibel verwendet werden. Ebenfalls betrifft die Erfindung ein Verfahren zum Durchführen einer OCT-Messung.

Interferometric encoder using spectral analysis

OPTICAL INTERFEROMETRIC PROCESS OF MEASUREMENT OF the DEVIATION OF the SURFACE Of a TEST-TUBE UNDER the INFLUENCE OF the ULTRASOUNDS

Interferometer

Improvements with the interferometers with separate beams

Process and Device for Generating an Output Pulse-Train

INTERFEROMETRIC MEASURING DEVICE

METHOD AND DEVICE FOR MICROSCOPY INTERFERENTIAL HIGH RESOLUTION FULL-FIELD

EXTRINSIC FIBER OPTIC DEVICE FOR MEASURING A PHYSICAL PARAMETER

Optical Distance-Measuring Device

An optical distance-measuring device includes a light source and an interferometer unit having a measuring retroreflector, a stationary reference retroreflector, a beam-splitter element, a beam-recombiner unit and a detection unit. The beam of rays emitted by the light source is able to swivel about the center of the reference retroreflector. The beam of rays arriving from the light source is split via the beam-splitter element into at least one measuring beam of rays and one reference beam of rays. The at least one measuring beam of rays propagates in the direction of the measuring retroreflector, and the reference beam of rays propagates collinearly with respect to the measuring beam of rays in the direction of the reference retroreflector. The measuring beam of rays is reflected back by the measuring retroreflector and the reference beam of rays is reflected back by the reference retroreflector in the direction of the beam-recombiner unit, the measuring beam of rays traveling symmetrically relative to the reference retroreflector prior to and after reflection at the measuring retroreflector. The beam-recombiner unit brings the measuring beam of rays and the reference beam of rays to interference. Distance-dependent interference signals are ascertainable via the detection unit.

Устройство спектроскопической оптической когерентной томографии эндоскопическим зондом

Полезная модель относится к области измерительной техники и касается устройства спектроскопической оптической когерентной томографии эндоскопическим зондом. Устройство содержит плечо источника излучения, опорное плечо, плечо образца и плечо детектора излучения, принимающего пучки излучения из опорного плеча и плеча образца. Для формирования зондирующего излучения используется сочетание широкополосного фемтосекундного титан-сапфирового лазера с перестраиваемым оптическим фильтром Фабри-Перо, а для детектирования отраженного и рассеянного излучения применен широкополосный спектрометр. Синхронизация работы плеча образца и плеча детектора организована посредством оптического триггера. Технический результат заключается в повышении точности детектирования интерференционного сигнала и увеличении информативности получаемых изображений. РОССИЙСКАЯ ФЕДЕРАЦИЯ (19) RU (11) (13) 196 595 U1 (51) МПК G01B 9/02 (2006.01) G01N 21/39 (2006.01) ФЕДЕРАЛЬНАЯ СЛУЖБА ПО ИНТЕЛЛЕКТУАЛЬНОЙ СОБСТВЕННОСТИ (12) ОПИСАНИЕ ПОЛЕЗНОЙ МОДЕЛИ К ПАТЕНТУ (52) СПК G01B 9/02091 (2019.08); G01N 21/39 (2019.08) (21)(22) Заявка: 2019141025, 12.12.2019 (24) Дата начала отсчета срока действия патента: 06.03.2020 Приоритет(ы): (22) Дата подачи заявки: 12.12.2019 (45) Опубликовано: 06.03.2020 Бюл. № 7 (54) Устройство спектроскопической оптической когерентной томографии эндоскопическим зондом (57) Реферат: Полезная модель относится к области перестраиваемым оптическим фильтром Фабриизмерительной техники и касается устройства Перо, а для детектирования отраженного и спектроскопической оптической когерентной рассеянного излучения применен томографии эндоскопическим зондом. широкополосный спектрометр. Синхронизация Устройство содержит плечо источника излучения, работы плеча образца и плеча детектора опорное плечо, плечо образца и плечо детектора организована посредством оптического триггера. излучения, принимающего пучки излучения из Технический результат заключается в повышении опорного плеча и плеча образца. Для ...

Устройство для измерения радиуса оптической сферической поверхности

Полезная модель относится к измерительной технике и может быть использована в устройствах для измерения радиуса оптических сферических поверхностей, а также при контроле оптических деталей как в процессе их изготовления, так и после него. Сущность: устройство для измерения радиуса оптической сферической поверхности содержит интерферометр Физо, состоящий из когерентного источника света, светоделительного элемента, коллиматора, объектива построения изображения интерферограмм, ПЗС камеры и эталонного объектива. В устройство введены дополнительный светоделительный элемент, установленный между коллиматором и эталонным объективом, и низкокогерентный интерферометр, включающий некогерентный источник света, светоделительный элемент низкогогерентного интерферометра, подвижное зеркало, фотодиод, линейный энкодер низкокогерентного интерферометра. При этом низкокогерентный интерферометр связан с дополнительным светоделительным элементом таким образом, что пучок света от низкокогерентного интерферометра падает на дополнительный светоделительный элемент, при этом радиус контролируемой поверхности равен сумме или разности между радиусом эталонной поверхности и расстоянием L между эталонной и контролируемой поверхностями, измеряемым низкокогерентным интерферометром. Благодаря конструктивному решению устройства появилась возможность измерения радиуса контролируемой поверхности путем измерения расстояния между контролируемой и эталонной поверхностями в конфокальной позиции. 7 ил. РОССИЙСКАЯ ФЕДЕРАЦИЯ (19) RU (11) (13) 200 479 U1 (51) МПК G01B 9/02 (2006.01) G01B 11/24 (2006.01) ФЕДЕРАЛЬНАЯ СЛУЖБА ПО ИНТЕЛЛЕКТУАЛЬНОЙ СОБСТВЕННОСТИ (12) ОПИСАНИЕ ПОЛЕЗНОЙ МОДЕЛИ К ПАТЕНТУ (52) СПК G01B 9/02 (2020.08); G01B 9/02027 (2020.08); G01B 11/24 (2020.08); G01B 11/2408 (2020.08); G01B 11/2441 (2020.08) (21)(22) Заявка: 2020125334, 22.07.2020 22.07.2020 (73) Патентообладатель(и): Общество с ограниченной ответственностью "Опто - Технологическая Лаборатория" (ООО "Опто - ТЛ") (RU) Дата регистрации: ...

Интерферометр для измерения пространственной когерентности

Полезная модель относится к оптическим устройствам, а именно к интерферометрам, позволяющим измерять пространственную когерентность светового, в том числе лазерного излучения. Техническим результатом является повышение точности измерений степени пространственной когерентности интерферометром за счет обеспечения повышения контраста интерференционной картины. Технический результат достигается за счет того, что интерферометрдля измерения пространственной когерентности содержит последовательно расположенные первую призму Глана, первый кристалл исландского шпата, выполненный с возможностью вращения вокруг своей оптической оси, а также с возможностью формирования обыкновенного и необыкновенного лучей, второй кристалл исландского шпата, размещенный так, что его оптическая ось перпендикулярна оси первого кристалла шпата, вторую призму Глана, выполненную с возможностью вращения вокруг оси исходного луча, диафрагму и регистрирующее устройство. При этом интерферометр содержит размещенный между вторым кристаллом исландского шпата и второй призмой Глана фазовый электрооптический модулятор, а диафрагма установлена на подвижном держателе с возможностью совмещения ее центра с необыкновенным или обыкновенным лучом. 3 з.п. ф-лы, 1 ил. РОССИЙСКАЯ ФЕДЕРАЦИЯ (19) RU (11) (13) 205 419 U1 (51) МПК G01B 9/02 (2006.01) ФЕДЕРАЛЬНАЯ СЛУЖБА ПО ИНТЕЛЛЕКТУАЛЬНОЙ СОБСТВЕННОСТИ (12) ОПИСАНИЕ ПОЛЕЗНОЙ МОДЕЛИ К ПАТЕНТУ (52) СПК G01B 9/02062 (2021.02) (21)(22) Заявка: 2020144153, 30.12.2020 (24) Дата начала отсчета срока действия патента: Дата регистрации: 14.07.2021 Приоритет(ы): (22) Дата подачи заявки: 30.12.2020 (45) Опубликовано: 14.07.2021 Бюл. № 20 2 0 5 4 1 9 R U (54) ИНТЕРФЕРОМЕТР ДЛЯ ИЗМЕРЕНИЯ ПРОСТРАНСТВЕННОЙ КОГЕРЕНТНОСТИ (57) Реферат: Полезная модель относится к оптическим формирования обыкновенного и устройствам, а именно к интерферометрам, необыкновенного лучей, второй кристалл позволяющим измерять пространственную исландского шпата, размещенный так, что его когерентность светового, в ...

Systems, Methods and Computer-Accessible Medium Which Provide Microscopic Images of at Least One Anatomical Structure at a Particular Resolution

Exemplary embodiments of apparatus, systems and methods can be provided for providing at least one electro-magnetic radiation to at least one sample. For example, a plurality of wave-guiding arrangements can be provided which are configured to (i) provide the electro-magnetic radiation(s), and (ii) at a point of emission of each of the wave guiding arrangements, cause a phase of each of the electro-magnetic radiation(s) to have a predetermined value. The exemplary apparatus can be part of a probe. Further the exemplary apparatus can include an interferometric arrangement provided in communication with the probe and/or be part of the probe.

Method and system for measuring patterned structures

A method and system are presented for determining a line profile in a patterned structure, aimed at controlling a process of manufacture of the structure. The patterned structure comprises a plurality of different layers, the pattern in the structure being formed by patterned regions and un-patterned regions. At least first and second measurements are carried out, each utilizing illumination of the structure with a broad wavelengths band of incident light directed on the structure at a certain angle of incidence, detection of spectral characteristics of light returned from the structure, and generation of measured data representative thereof. The measured data obtained with the first measurement is analyzed, and at least one parameter of the structure is thereby determined. Then, this determined parameter is utilized, while analyzing the measured data obtained with the second measurements enabling the determination of the profile of the structure

Imaging apparatus and imaging method

An imaging apparatus includes changing unit for changing a positional relation of irradiation positions of a plurality of measuring beams to be radiated onto an object. The imaging apparatus includes scanning unit for scanning the plurality of measuring beams in the positional relation which has been changed by the changing unit, and acquiring unit for acquiring an optical coherence tomographic image of the object on the basis of the plurality of measuring beams.

Image acquisition apparatus, image acquisition system, and method of controlling the same

An OCT apparatus that photographs with a plurality of measuring beams concurrently has a mechanism for adjusting the optical path length of a reference beam for each measuring beam. Accordingly, when tomographic images photographed in this manner are displayed side by side, because the depth of photographing varies from one tomographic image to another, it is difficult for an operator to comprehend the positional relation between the photographed images. In displaying tomographic images acquired with a plurality of measuring beams, the display position of each tomographic image is adjusted based on the changed optical path length of a reference beam of the measuring beam used for the image. The tomographic images are thus aligned in height and are presented in a manner that is easy for the operator to comprehend the positional relation between the photographed images.

Hybrid Spectral Domain Optical Coherence Tomography Line Scanning Laser Ophthalmoscope

A method of imaging a retina of an eye includes combining an optical path of an optical coherence tomography (OCT) imager and an optical path of a line scanning laser ophthalmoscope (LSLO) imager using a system of optics. The method also includes using a single detector to switch between an OCT mode and a LSLO mode and acquiring images of the retina while switching between the OCT mode and the LSLO mode.

Physical state measuring apparatus and physical state measuring method

The physical state measuring apparatus includes: a light source; a transmitting unit which transmits a light from the light source to a measurement point of an object to be measured; a nonlinear optical device which changes a wavelength of the light reflected by the measurement point to a wavelength that is different from the wavelength before the changing; a light receiving unit which receives the light whose wavelength has been changed; and a measuring unit which measures a physical state of the object to be measured at the measurement point based on a waveform of the light received by the light receiving unit.

Imaging device and imaging method

The present invention relates to a structure in which a sensor includes a first area and a second area upon which dispersed first and second lights are focused. The first and second areas are disposed in a dispersion direction or a direction perpendicular to the dispersion direction. A distance between the first and second areas is adjusted by using a distance between a plurality of fiber ends from which a plurality of combined lights exit and an optical magnification at a detecting section.

Electronically Controlled Fixation Light for Ophthalmic Imaging Systems

An electronically controlled fixation light system is described for ophthalmic systems. The ophthalmic system can include an ophthalmic imaging device that generates an image of a portion of an imaged eye, a fixation light controller that includes an input module, configured to receive an input in relation to the image generated by the ophthalmic imaging device, and a control signal generator that generates an electronic fixation light control signal in response to the received input, and a fixation light source, configured to receive the fixation light control signal, and to generate a fixation light according to the received fixation light control signal. A surgeon can image a portion of an eye with the imaging device, determine a misalignment of the imaged eye relative to the imaging device based on the image, and control the fixation light with an electronic control signal to reduce the determined misalignment.

Methods for mapping tissue with optical coherence tomography data

Various methods are disclosed for mapping optical coherence tomography (OCT) data to facilitate review and diagnosis. In one aspect, high resolution 2D line scans are obtained along with lower density 3D cube scans and displayed in a manner to provide context to the clinician. In another aspect, OCT data is analyzed to provide information about non-uniformities of the tissue. Binary image maps of maps useful for determining tautness of membranes are also disclosed.

Systems and Methods for Surgical Microscope and Optical Coherence Tomography (OCT) Imaging

A surgical microscope assembly includes a microscope main objective and microscope imaging optics. The microscope main objective and microscope imaging optics define a viewing beam path that passes from a sample through the microscope main objective and the microscope imaging optics. The assembly includes an optical coherence tomography (OCT) unit having an illumination beam and a collection beam and a beamsplitter between the microscope main objective and the microscope imaging optics. The beamsplitter is configured to direct a portion of light from the microscope main objective to the microscope imaging optics and to direct another portion of light from the microscope main objective to the OCT unit collection beam. The beamsplitter is further configured to direct an illumination beam from the OCT unit to the microscope main objective and to the sample. A beam forming unit is between the OCT unit and the beamsplitter. The beam forming unit is configured to form the illumination beam of the OCT unit so as to generally correspond to a size of the microscope main objective.

Laser-based coordinate measuring device and laser-based method for measuring coordinates

A laser based coordinate measuring device measures a position of a remote target. The laser based coordinate measuring device includes a stationary portion, a rotatable portion, and at least a first optical fiber. The stationary portion has at least a first laser radiation source and at least a first optical detector, and the rotatable portion is rotatable with respect to the stationary portion. The first optical fiber system, which optically interconnects the first laser radiation source and the first optical detector with an emission end of the first optical fiber system, has the emission end disposed on the rotatable portion. The emission end emits laser radiation to the remote target and receives laser radiation reflected from the remote target with the emission direction of the laser radiation being controlled according to the rotation of the rotatable portion.

Interference microscope and measuring apparatus

In an interference microscope and a measuring device for observing and inspecting the surface and inside of a specimen such as a wafer by applying laser light to the specimen and using an interferometer, a reference optical path for conducting light is provided between a beam splitter and a reference mirror, and a measurement optical path for conducting light is provided between the beam splitter and the specimen, thereby providing an optical path difference between the reference optical path and the measurement optical path. Further, the reference mirror is tilted slightly, thereby forming interference fringes on detection means. It is possible to measure the surface shape of the specimen (measurement object) such as a wafer only by slightly tilting the reference mirror with a simple configuration and locate the accurate coordinate positions of foreign particles and pole pieces.

Image processing apparatus and method

An image processing apparatus which processes a plurality of tomograms obtained by acquiring, along a direction crossing at a right angle a section along the thickness direction of a retina, a plurality of tomograms each including the section, detects a layer structure in the retina from image information of respective lines of the tomograms along the thickness direction, and appends structure information to the respective lines based on the layer structures detected for the respective lines. The image processing apparatus maps the structure information of the respective lines of the plurality of tomograms onto a plane crossing the thickness direction at a right angle, thereby generating a two-dimensional image based on the structure information.

Optical system, in particular in a microlithographic projection exposure apparatus

An optical system, such as a microlithographic projection exposure apparatus, includes a first optical component, a second optical component, and a measurement arrangement for determining the relative position of the first optical component and the second optical component in six degrees of freedom. The measurement arrangement is adapted to determine the relative position of the first optical component and the second optical component over six different length measurement sections. The length measurement sections extend directly between the first optical component and the second optical component.

Image processing apparatus for processing tomographic image of subject's eye, imaging system, method for processing image, and recording medium

An image processing apparatus includes a detection unit configured to detect layers on the retina based on tomographic images of the retina, an acquisition unit configured to acquire a region having a larger curvature of the boundary surface between the retina and the corpus vitreum than a threshold value, and a determination unit configured to determine an optic disc of the retina based on the optical disc including a region where a specific layer is not detected by the detection unit and the region acquired by the acquisition unit.

Actively Mode Locked Laser Swept Source for OCT Medical Imaging

An optical coherence analysis system uses a laser swept source that is constrained to operate in a mode locked condition. This is accomplished by synchronously changing the laser cavity's gain and/or phase based on the round trip travel time of light in the cavity. This improves high speed tuning by taking advantage of frequency shifting mechanisms within the cavity and avoids chaotic laser behavior.

Integrated OCT Detector System with Transimpedance Amplifier

An optical detector system comprises a hermetic optoelectronic package, an optical bench installed within the optoelectronic package, a balanced detector system installed on the optical bench. The balanced detector system includes at least two optical detectors that receive interference signals. An electronic amplifier system installed within the optoelectronic package amplifies an output of at least two optical detectors. Also disclosed is an integrated optical coherence tomography system. Embodiments are provided in which the amplifiers, typically transimpedance amplifiers, are closely integrated with the optical detectors that detect the interference signals from the interferometer. Further embodiments are provided in which the interferometer but also preferably its detectors are integrated together on a common optical bench. Systems that have little or no optical fiber can thus be implemented.

System and method for measuring a distance

This disclosure provides systems, methods and apparatus, including computer programs encoded on computer storage media, for measuring a distance. In one aspect, the method includes actuating or releasing an interferometric modulator having a first surface and a second surface and measuring a distance between the first and second surfaces at a plurality of times during the actuation or release. In another aspect, the method includes illuminating, with a first laser beam having a first wavelength and with a second laser beam having a second wavelength different from the first wavelength, an interferometric modulator having a distance between a first surface which is at least partially reflective and a second surface which is at least partially absorptive, measuring a first intensity of the first laser beam modulated by the interferometric modulator and a second intensity of the second laser beam modulated by the interferometric modulator, and determining the distance based on the measured intensities.

Multi-path spectrometer

A spectrometer in accordance with the present disclosure may provide multiple optical paths from the inputs to the camera, where the paths are as nearly identical as possible. For example, a spectrometer in accordance with the present disclosure may include multiple inputs, input optics, a diffraction grating, output optics, and a camera. The multiple inputs may be imaged onto different sections of the camera using the same input optics, the same diffraction grating, and the same output optics.

Apparatus for the absolute measurement of two dimensional optical path distributions using interferometry

An apparatus for the absolute measurement of a two dimensional optical path distribution comprising: a light source ( 4 ) for illuminating an object ( 26 ) with light having a plurality of wavelengths: an interferometer ( 12 ) for forming an image of at least part of the object, which image comprises a broad band interferogram; a hyperspectral imager ( 30 ) in optical communication with the interferometer for spectrally separating the broad band interferogram into a plurality of narrow band two dimensional interferograms ( 72, 74, 76 ); a register ( 38 ) for spatially registering the narrow band interferograms; an extractor for extracting one dimensional intensity signals from corresponding pixels in each narrow band interferogram; and a calculator ( 100 ) for calculating the frequency for each point on the object from a one dimensional intensity signal associated with that point.

Spectral reflectometry method and device

The invention relates to optical low-coherence reflectometry with spectral reception and may be used for obtaining images without coherent noise caused by self-interference of the radiation scattered from the studied object and by spurious reflections in the optical path of the system. Two or more consecutive measurements of the interference spectrum are made. During at least one measurement of the interference spectrum by means of the interference control unit the phase between the interfering parts of the radiation is modulated by a certain law during exposure, which results in averaging and, hence, zeroing of the cross-correlation (useful) component of the registered spectrum, and during at least one additional measurement of the interference spectrum, the phase between the interfering parts of the radiation is not modulated during exposure. The phase between the interfering parts of the radiation may be set to be different in additional measurements of the interference spectrum. The invention allows coherent noise to be fully eliminated without loss of the radiation power scattered by the object.

Common detector for combined raman spectroscopy-optical coherence tomography

In one aspect of the present invention, an apparatus includes a first light source for generating a broadband light, and a second light source for generating a monochromatic light, a beamsplitter optically coupled to the first light source for receiving the broadband light and splitting the received broadband light into a reference light and a sample light, a reference arm optically coupled to the beamsplitter for receiving the reference light and returning the received reference light into the beamsplitter, and a sample arm optically coupled to the beamsplitter and the second light source for combining the sample light and the monochromatic light, delivering the combined sample and monochromatic light to the target of interest, collecting a backscattering light and a Raman scattering light that are generated from interaction of the sample light and the monochromatic light with the target of interest, respectively, returning the backscattering light into the beamsplitter so as to generate an interference signal between the returned backscattering light and the returned reference light in the beamsplitter, and directing the Raman scattering light in an output optical path, and a single detector optically coupled to the beamsplitter for collecting the interference signal.

Image forming method and optical coherence tomograph apparatus using optical coherence tomography

An image forming method uses an optical coherence tomography as to an optical axis direction of plural pieces of image information of an object. First image information of an object is obtained at a first focus with respect to an optical axis direction to then object. A focusing position is changed by dynamic focusing from the first focus to a second focus along the optical axis. The second image information of the object is obtained at the second focus. A third image information, tomography image information of the object and including a tomography image of the first focus or the second focus, is obtained by Fourier domain optical coherence tomography. A tomography image or a three-dimensional image of the object is formed in positional relation, in the optical axis direction, between the first image information and the second image information using the third image information.

Systems and methods for signal processing in optical imaging systems

Systems, devices and methods of producing an image are provided. A electro-magnetic radiation source provides electro-magnetic radiation to a sample and a reference. A detector/interferogram unit produces at least one interferogram that is supplied to a signal processing unit. The signal processing unit extracts phase, magnitude, and/or polarization data from the supplied signals, and produces an image based on at least the extracted data.

Multi-Point Interferometric Phase Change Detection Method

Provided is a method for measuring multi-point interferometric angle changes beginning with an interferometric device capable of measuring at least one main point and at least one reference point. The method includes recording interferometric intensity changes on two or more spots using the main point and the reference point, and determining a sequence having a plurality of peak, local maximas and a plurality of valley, local minimas. The method includes sampling a first, partial sequence and comparing it to a neighboring, partial sequence using a perturbation analysis and additional calculation(s) to compile all phase angle changes for all measured points. Also provided is a computer implemented method to enable nanometer resolution sensitivity in a noisy signal and for characterization of a material in an interferometric device.

Photographing apparatus and photographing method

The present invention provides an ophthalmological apparatus capable of displaying a plurality of fundus tomographic images. A photographing apparatus includes a fundus imaging unit adapted to capture a fundus image of a subject's eye, a scanning unit adapted to scan a desired position of the fundus of the subject's eye to capture tomographic images of the subject's eye, a measuring unit adapted to measure movement amounts of the fundus of the subject's eye by performing pattern matching between a plurality of feature points in the acquired fundus image and feature points in another fundus image newly acquired at a different time, and a control unit adapted to control the scanning unit based on the measured movement amounts.

Image photographing apparatus and image photographing method

An image photographing apparatus includes; an acquiring unit configured to acquire an image of an eye to be inspected, a measuring unit configured to measure movement of the eye to be inspected based on the image, a predicting unit configured to predict the movement of the eye to be inspected based on a cycle of the movement of the eye to be inspected which has been measured by the measuring unit, and a control unit configured to control an acquisition position where the acquiring unit acquires the image based on the movement of the eye to be inspected which has been predicted by the predicting unit.

Polarization interferometer

An interferometer includes an optical assembly for directing an input optical field, a space-variant polarization converter, and an analyzer. The optical assembly is configured and operable to produce first and second spatially separated optical fields of incident coherent radiation of substantially the same intensity and different polarizations and to define first and second spatially separated optical paths for propagation of said first and second optical fields thereby allowing interaction between the first optical field and an element affecting a phase thereof in said first optical path. The space-variant polarization converter is accommodated in said combined path and being configured and operable to simultaneously apply space-variant polarization conversion to two beams corresponding to combined first and second optical fields having different polarizations and produce radially and azimuthally polarized beams respectively. The analyzer is located downstream of said polarization converter.

Interferometric quasi-autocollimator

Systems and method are disclosed for measuring small angular deflections of a target using weak value amplification. A system includes a beam source, a beam splitter, a target reflecting surface, a photodetector, and a processor. The beam source generates an input beam that is split into first and second beams by the beam splitter. The first and second beams are propagated to the target reflecting surface, at least partially superimposed at the target reflecting surface, and incident to the target reflecting surface normal to the target reflecting surface. The first beam is reflected an additional even number of times during propagation to the photodetector. The second beam is reflected an additional odd number of times during propagation to the photodetector. The first and second beams interfere at the photodetector so as to produce interference patterns. The interference patterns are interpreted to measure angular deflections of the target reflecting surface.

Control apparatus, imaging control method, and storage medium

A control apparatus of an imaging apparatus, includes a selection unit configured to select an image-capturing site of a subject to be examined, a control unit configured to control adjustment of a member of the imaging apparatus, according to the selected image-capturing site, and a determination unit configured to determine whether to perform the adjustment or not in response to a change of image-capturing sites through the selection by the selection unit, based on image-capturing conditions for the image-capturing sites before and after the change of the image-capturing sites.

Fiber optic transducers, fiber optic accelerometers and fiber optic sensing systems

A fiber optic transducer is provided. The fiber optic transducer includes a fixed portion configured to be secured to a body of interest, a moveable portion having a range of motion with respect to the fixed portion, a spring positioned between the fixed portion and the moveable portion, and a length of fiber wound between the fixed portion and the moveable portion. The length of fiber spans the spring. The fiber optic transducer also includes a mass engaged with the moveable portion. In one disclosed aspect of the transducer, the mass envelopes the moveable portion.

Systems and methods for endoscopic angle-resolved low coherence interferometry

Fourier domain a/LCI (faLCI) system and method which enables in vivo data acquisition at rapid rates using a single scan. Angle-resolved and depth resolved spectra information is obtained with one scan. The reference arm can remain fixed with respect to the sample due to only one scan required. A reference signal and a reflected sample signal are cross-correlated and dispersed at a multitude of reflected angles off of the sample, thereby representing reflections from a multitude of points on the sample at the same time in parallel. Information about all depths of the sample at each of the multitude of different points on the sample can be obtained with one scan on the order of approximately 40 milliseconds. From the spatial, cross-correlated reference signal, structural (size) information can also be obtained using techniques that allow size information of scatterers to be obtained from angle-resolved data.

Four-dimensional optical coherence tomography imaging and guidance system

A four-dimensional optical coherence tomography imagining and guidance system includes an optical coherence tomography system, a data processing system adapted to communicate with the optical coherence tomography system, and a display system adapted to communicate with the data processing system. The optical coherence tomography system is configured to provide data corresponding to a plurality of volume frames per second. The data processing system is configured to receive and process the data and provide three-dimensional image data to the display system such that the display system displays a rendered real-time three-dimensional image.

Method and device for measuring motion error of linear stage

Measurement of motion errors of a linear stage is performed to enable accurate measurement of motion errors in linear directions and a rotational direction in the linear stage using a diffraction grating. A first beam splitter splits a laser beam emitted from a light emitting unit. A first measurement unit measures a unidirectional linear motion error of the linear stage using one laser beam component split by the first beam splitter and a second measurement unit measures an angular motion error and another unidirectional linear motion of the linear stage error using a diffracted beam component obtained by diffracting another laser beam component split by the first beam splitter through the diffraction grating. A third measurement unit circularly polarizes the beam component diffracted through the diffraction grating to measure a third unidirectional linear motion error of the linear stage.

Optical coherence tomographic imaging apparatus, optical coherence tomographic imaging method, program for executing the optical coherence tomographic imaging method, and storage medium having the program stored thereon

In order to perform accurate evaluation for enhanced depth imaging (EDI) in which a tomographic image of a retina has a low luminance value in large part, provided is an optical coherence tomographic imaging apparatus for acquiring an image of an object to be inspected by irradiating the object to be inspected with measuring light and causing return light from the object to be inspected to interfere with reference light, the optical coherence tomographic imaging apparatus including: a unit for setting an imaging parameter of the image; a unit for selecting an image quality evaluation index in accordance with the imaging parameter; a unit for acquiring an image characteristic amount from the acquired image in accordance with the set imaging parameter; and a unit for evaluating image quality of the image based on the image characteristic amount and the image quality evaluation index.

Imaging apparatus and imaging method

An imaging apparatus capturing optical coherence tomographic images of a test object based on a plurality of combined light beams that are obtained by combining a plurality of return light beams from the test object irradiated with a plurality of measurement light beams and a plurality of reference light beams respectively corresponding to the plurality of measurement light beams, the apparatus including: an instruction unit configured to give instructions about amounts of changes in respective optical path length differences between the plurality of reference beams and the plurality of return light beams; and a change unit configured to change the optical path length differences based on the amounts of changes instructed by the instruction unit.

System and Method for Interlacing Differing Coherence Length Sweeps to Improve OCT Image Quality

A system and method for sweeping electromagnetic radiation over a first coherence length and a second length over a range of wavelengths to generate an image. Electromagnetic radiation having a first coherence length is generated and swept over a range of wavelengths. Electromagnetic radiation having a second coherence length is generated and swept over a range of wavelengths. The electromagnetic radiation is splitting through a reference path and a sample path; Electromagnetic radiation returned from the reference path and the sample path is detected, wherein the detector generates output signals corresponding to the received electromagnetic radiation. In one embodiment, the output signals are processed to generate an image. The image may be interleaved with data corresponding to the electromagnetic radiation having the first coherence length and the second coherence length.

In situ calibration of interferometers

In-situ calibration of an interferometer includes making a sequence of phase measurements of a test object using the interferometer, each of the measurements having a same carrier fringe frequency, where at least some of the measurements are made at three or more different orientations of carrier fringes, and determining information about the test object based on at least some of the phase measurements, in which determining the information includes reducing errors in the measurements arising from imperfections in the interferometer based on the measurements made at the three or more different orientations.

PROBE FOR OPTICAL TOMOGRAPIC IMAGE MEASUREMENT DEVICE AND METHOD FOR ADJUSTING PROBE

A prism is attached to a refractive index dispersion lens by inclining the incident plane of the prism by a prescribed angle with respect to the end face of the refractive index dispersion lens and filling adhesive therebetween. In this way, the amount of light reflected from the bottom plane of the prism decreases in accordance with the angle of inclination of the incident plane, and the interference signal formed by the reflected light from the bottom plane of the prism, and the reflected light of a reference beam therefore weakens and the image signal decreases. Consequently, distinguishing between the image signal and the image signals produced by reflected light from the measurement subject is facilitated. 117-. (canceled)18. A probe for an optical tomographic image measurement device , wherein the optical tomographic image measurement device includes a main body for obtaining an optical tomographic image of a measurement subject , and the probe for guiding measurement beams to the measurement subject , wherein the optical tomographic image measurement device further includes:a light beam source for emitting low coherent beams;a light beam dividing means for dividing the low coherent beams emitted from the light beam source into measurement beams and reference beams;a reflection mirror for reflecting the reference beams divided by the light beam dividing means, and for giving a predetermined optical path length to the reference beams;an optical multiplexing means for multiplexing measured reflected beams returning from the measurement subject at a time when the measurement beams from the probe are radiated onto the measurement subject, and the reference beams reflected by the reflection mirror; andan optical interfering beam detection means for detecting optical interfering beams which are interfered with the measured reflected beams multiplexed by the optical multiplexing means and the reference beams,wherein the probe comprises an optical member having a ...

Measuring apparatus

A measuring apparatus includes a light source unit configured to continuously scan wavelengths of a plurality of types of beams at different speeds in a plurality of discrete wavelength scanning ranges, a beam synthesizer, an interferometer unit configured to detect as an interference signal an interference fringe formed by a reference beam reflected on a reference surface and a target beam reflected on a target surface, and a processor configured to determine the absolute distance based upon the interference signal detected by the interferometer unit. The interferometer unit includes a single optical detector. The processor obtains the absolute distance for each of the plurality of types of beams through a frequency analysis of a synthesized interference signal, and outputs one absolute distance by operating a plurality of absolute distances that have been obtained.

Surface shape measurement method and surface shape measurement apparatus

The present surface shape measurement method includes: splitting white light that includes different wavelengths into reference light and measurement light; causing the measurement light to enter a measurement target plane; causing the reference light to enter a first diffraction grating; combining the reference light having passed through a first optical path from the first diffraction grating to enter a second diffraction grating and thereafter having passed through the first optical path from the second diffraction grating to enter the first diffraction grating to be output from the first diffraction grating and the measurement light reflected from the measurement target plane, to form interfering light, to thereby measure a surface shape of the measurement target plane.

Observation Device and Method of Observing

Provided is an observation device and a method of observing capable of clearly obtaining information relating to a boundary part where a medium inside an observation object changes. An observation device () is a device for observing an observation object () including a sensitivity factor in which a dipole moment changes by sensing an electromagnetic wave (). An output part () outputs the electromagnetic wave () and the dipole moment of the sensitivity factor included in the observation object () is changed by the electromagnetic wave (). A detector part () detects, of the electromagnetic wave () outputted from the output part (), a signal electromagnetic wave () which comes through the observation object () and a reference electromagnetic wave () which bypasses the observation object (). A control part () analyzes the structure of the observation object () based on the detection results of the detection part (). The electromagnetic wave () is pulse laser light which is intermittently outputted in pulse waveform. The wavelength of the electromagnetic wave () is arranged within the wavelength absorption band of the sensitivity factor. 1. An observation device for observating an observation object , including an induction factor whose dipole moment changes by induction with an electromagnetic wave , the device comprisingan output part which outputs an electromagnetic wave and changes the dipole moment of said induction factor included in said observation object by the outputted electromagnetic wave;a detection part which detects a signal electromagnetic wave coming through said observation object and a reference electromagnetic wave coming without passing through said observation object among electromagnetic waves outputted by said output part; andan analysis part which analyzes structures of said observation object based on detection result by said detection part,wherein said electromagnetic wave outputted by said output part is a pulsed laser light which is ...

SYSTEMS AND METHODS FOR SUPPRESSING COHERENT STRUCTURED ILLUMINATION ARTIFACTS

Methods and systems are provided for suppressing speckle and/or diffraction artifacts in coherent structured illumination sensing systems. A coherent radiation pattern forms an interference pattern at an illumination image plane and illuminates an object. Radiation scattered or otherwise emitted by the object is detected to produce a signal, which is integrated in time. Coherent artifact suppression is attained by using a spatial modulator, such as an acousto-optic device, to vary a phase gradient at the illumination image plane during the signal integration time. Various embodiments are provided for purposes including without limitation: preserving the depth of field of the coherent illumination; using the same acousto-optic device for pattern generation and coherent artifact suppression; electronically controlling the effective spatial coherence of the illumination system; and reducing errors due to coherent artifacts in a laser-based three dimensional imaging system. 1. A method of suppressing at least one of speckle and a diffraction artifact sensed by a detector , the method comprising:illuminating an object with a first radiation, the first radiation forming an interference pattern at an illumination image plane, so as to produce a second radiation from the object;sensing at least a portion of the second radiation with the detector so as to produce a signal representative of the sensed second radiation;temporally integrating the signal over an integration period; andimparting a phase gradient across the first radiation at the illumination image plane, the phase gradient varying in time during the integration period.2. The method recited in further comprising:varying the phase gradient using at least one of a tilting mirror, a micromirror array, a grating light valve, and a liquid crystal spatial light modulator.3. The method recited in further comprising:varying the phase gradient using an acousto-optic device driven with a drive signal, the acousto-optic ...

OBSERVATION DEVICE

Provided is an observation device which can obtain a phase image of a moving object rapidly with high sensitivity even when using a photodetector having a slow read-out speed per pixel. The observation device comprises a light source , a first modulator , a second modulator , a lens , a beam splitter , a photodetector , and an arithmetic unit . The lens receives scattered light generated by a moving object and forms a Fourier transform image of the object . The photodetector outputs data representing a sum in a v direction of data temporally changing at a frequency corresponding to a Doppler shift frequency of the light having reached each position on a light-receiving surface through the lens at each position in a u direction at each time. The arithmetic unit obtains an image of the object according to the output of the photodetector 1: An observation device comprising:a light source for irradiating a moving object with light;a detection unit, letting a first direction be a direction on a predetermined plane yielding a fixed Doppler shift effect caused by a movement of the object in light having reached the predetermined plane in scattered light generated by the object upon irradiation with the light by the light source while being perpendicular to a moving direction of the object and a second direction be a direction orthogonal to the first direction on the predetermined plane while being parallel to the moving direction of the object, for outputting data representing a sum in the second direction of data temporally changing at a frequency corresponding to a Doppler shift frequency of the light having reached each position on the predetermined plane at each position in the first direction at each time; andan arithmetic unit for performing a one-dimensional Fourier transform of data employing the position in the first direction on the predetermined plane and time as variables with respect to a time variable and a two-dimensional Fourier transform of the Fourier- ...

COHERENCE GRID -- INTERFEROMETER AND METHOD FOR A SPATIALLY RESOLVED OPTIC MEASUREMENT OF THE SURFACE GEOMETRY OF AN OBJECT

A coherence grid—interferometer for spatially resolved optic measurement of an object, with a light source, an interferometer, a path length—altering unit, and camera with a detection area. The interferometer cooperates with the light source and camera such that an outgoing beam is split into a measuring beam and a reference beam, the measuring beam is at least partially reflected by the object to the detection area of the camera and overlapped via a beam splitter with the reference beam such that the overlapped beams overlap the photo sensors in a planar fashion, and the optic path length—altering unit changes the optic path length of the measuring and/or reference beams. The path length—altering unit has a path scale and a path detector which detect a changing length of the optic path of the measuring and/or reference beams and the interferogram records are synchronized with the path measurement. 1. A coherence grid—interferometer for a spatially resolved optic measuring of data for elevation geometry of an object ,{'b': 2', '3', '2', '3', '2', '8', '7', '1', '1', '3', '8', '8', '11', '12', '11, 'comprising a light source (), an interferometer, a path length—altering unit, and a camera () with a detection area, said detection area comprises a plurality of locally different photo sensors, with the interferometer being embodied cooperating with the light source () and the camera () such that an outgoing beam emitted by the light source () is split into a measuring beam and a reference beam (), with the measuring beam () impinging the object () in a planar fashion and at least partially reflected and/or portions of the measuring beam scattered by the object () being returned to the detection area of the camera () back into a radiation path of the interferometer and overlapped with the reference beam () such that the overlapped measuring beam and reference beam () cover the plurality of photo sensors, and the optic path length—altering unit being embodied to change an ...

Systems for Extended Depth Frequency Domain Optical Coherence Tomography (FDOCT) and Related Methods

Systems for extended depth frequency domain optical coherence tomography are provided including a detection system configured to sample spectral elements at substantially equal frequency intervals, wherein a spectral width associated with the sampled spectral elements is not greater than one-half of the frequency interval. Related methods are also provided herein. 1. An extended depth Fourier Domain Optical Coherence Tomography (FDOCT) imaging system , the system comprising:an optical source having a bandwidth;an optical detection system having a first mode of operation configured to sample a first plurality of spectral elements within the bandwidth of the optical source at substantially equal optical frequency intervals, wherein the optical frequency interval is less than or equal to about 10.7 GHz and wherein a number of sampled elements is greater than or equal to 1024; anda reference arm, a sample arm and an optical combiner, the optical combiner being configured to couple the reference arm and the sample arm to the optical detection system,wherein a transform is applied to a set of the sampled first plurality of spectral elements to derive spatial domain data; andwherein a reference arm path length associated with the reference arm and a sample arm path length associated with the sample arm are configured to set a position of an image of a structure of a sample within a spatial domain image window.2. The system of :wherein the optical detection system further has a second mode of operation configured to sample a second plurality of spectral elements within the bandwidth of the optical source;wherein a transform is applied to a set of the sampled second plurality of spectral elements to derive spatial domain data; andwherein the optical frequency interval of the set of the sampled second plurality of spectral elements in the second mode of operation is no less than two times wider than the optical frequency interval of the set of the sampled first plurality of ...

METHOD AND APPARATUS FOR OPTICAL IMAGING VIA SPECTRAL ENCODING

Exemplary method, apparatus and arrangement can be provided for obtaining information associated with a sample such as a portion of an anatomical structure. The information can be generated using first data, which can be based on a signal obtained from a location on the sample, and second data, where the second data can be obtained by combining a second signal received from the sample with a third reference signal. An image of a portion of the sample can also be generated based on the information. For example, the first data can be associated with spectral encoding microscopy data, and the second data can be associated with optical coherence tomography data. 1. An apparatus comprising:at least one first arrangement configured to provide first data associated with a first signal received from at least one region of at least one sample, wherein the region has a linear dimension that is not more than about 10 microns;at least one second arrangement configured to provide second data associated with a second signal received from the at least one sample and a third signal received from a reference; andat least one third arrangement configured to generate further data based on the first and second data.2. The apparatus according to claim 1 , wherein the at least one third arrangement is further configured to generate at least one of a two-dimensional image or a three-dimensional image based on the further data.3. The apparatus according to claim 1 , wherein the first and second data are obtained substantially simultaneously.4. The apparatus according to claim 1 , wherein the first and second data are associated with approximately the same location on the at least one sample.5. The apparatus according to claim 1 , wherein the first and second arrangements are provided in at least one of a probe or a single enclosure.6. The apparatus of claim 5 , further comprising a positioning arrangement configured to position at least one of the probe or the single enclosure at a ...

SYSTEMS AND METHODS FOR SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY

Systems and methods for increasing the duty cycle and/or producing interleaved pulses of alternating polarization states in swept-source optical coherence tomography (OCT) systems are considered. Embodiments including improved buffering, frequency selecting filter sharing among multiple SOAs, intracavity switching, and multiple wavelength bands are described. The unique polarization properties of the source configurations have advantages in speckle reduction, polarization-sensitive measurements, polarization state dependent phase shifts, spatial shifts, and temporal shifts in OCT measurements. 1. A swept source optical coherence tomography (OCT) system comprising:a light source arranged to generate a beam of pulses of light, wherein the source is operated at a duty cycle and wherein the wavelength of the light within each pulse varies over time;a first beam divider for separating the beam along first and second paths, said second path including a fiber delay line and followed by a Faraday rotator mirror for rotating the polarization of the light pulses in the second path and redirecting the pulses back through the fiber delay line;a beam combiner for combining the pulses traveling in the first path with polarization rotated pulses traveling in the second path onto a common path and with the length of the fiber delay line being selected so that a pulse train is created in the common path with pulses having an increased duty cycle relative to the duty cycle of the source;a second beam divider for separating the pulse train along a sample arm and a reference arm;optics for scanning the pulse train in the sample arm over a set of transverse locations on a sample;a first detector for measuring radiation returning from both the sample arm and the reference arm, the detector generating output signals in response thereto; anda processor for converting the output signals into image information.2. An OCT system as recited in claim 1 , wherein the Faraday rotator mirror is ...

APPARATUS FOR LOW COHERENCE OPTICAL IMAGING

The present invention relates to an apparatus for low coherence optical imaging, and more particularly to an apparatus for low coherence optical imaging which can obtain the information of the different depths of a sample simultaneously. The apparatus comprises a phase transformation unit or a beam shift unit. The phase transformation unit or beam shift unit transforms and reflects the reference light, such that the reflected reference light comprises different phases at the different positions of a cross-section. When the reference light and a information light from the sample are superimposed on a photo detector, the information of the different depths of the sample is obtained. By using the apparatus of the present invention, the elements, the volume, and the cost of the apparatus are reduced. Because of only two-dimensional scanning is required, the scanning rate is improved. 1. An apparatus for low coherence optical imaging , comprising:an optical source for providing a low coherence light beam;a main beam splitter for splitting the light beam to a sample light and a reference light, wherein the sample light is projected to a sample, and a portion of the sample light is reflected or scattered by the sample to form an information light, wherein the information light is directed to a photo detector by the main beam splitter;a phase transforming unit for reflecting the reference light to the photo detector and transforming the reference light to have different phases at different positions of a cross-section, wherein the reference light and the information light are superposed to form interference patterns on the photo detector; anda signal processing unit electrically coupled to the photo detector for analyzing the spatial information of the sample.2. The apparatus of claim 1 , wherein the phase transforming unit is a microstructure mirror.3. The apparatus of claim 2 , wherein the microstructure mirror is an optical grid.4. The apparatus of claim 1 , further ...

METHOD AND DEVICE FOR HIGH RESOLUTION FULL FIELD INTERFERENCE MICROSCOPY

The invention relates to an incoherent light full field interference microscopy device for the imaging of a volumetric scattering sample (). The device comprises an interference device () between a reference wave (), produced by reflection of an incident wave by a reflective surface () of a reference arm of the interference device, and an object wave () produced by backscattering of the incident wave by a slice of the sample, an acquisition device () for at least a first interference signal and at least a second interference signal resulting from the interference of the reference and object waves, the at least two interference signals having a phase difference, an processing unit () for calculating an image of the slice of the sample, based on said interference signals. The interference device also comprises an optical element () for modifying the phase of the wavefront, and the microscopy device comprises a control unit () for the optical element, linked to the processing unit (), the optical phase modification element being controlled by optimizing a statistical parameter of at least a part of the image calculated by the processing unit. 1. An incoherent light full field interference microscopy device for the imaging of a volumetric scattering sample , comprising:a source for emitting an incident wave having a given spectral band;an interference device comprising a reference arm and an object arm, to provide optical interference between a reference wave obtained by reflection of the incident wave on a reflective surface of the reference arm and an object wave obtained by the backscattering of the incident wave by a slice of the sample at a given depth of said sample, when said sample is placed in an object focal plane of a microscope objective placed in the object arm;a device for multichannel acquisition of at least a first interference signal and at least a second interference signal resulting from the optical interference of said reference and object waves, the ...

Electric field spectrum measurement device and object measurement device

Every depth of the measurement object measures energy structural information, refractive index, transmittance, reflectance other than property information of (as for the resolution several microns), e.g., space information at the same time. A spectrum measurement device receives a reference wave propagating in a reference path and a measurement wave propagating in a measurement path having a start point same as a start point of the reference path, and derives a spectrum of the measurement wave. The space information of the measuring object, energy structural information, refractive index, transmittance, a reflective index using spectrum measurement device are derived.

OPTICAL TOMOGRAPHIC IMAGING APPARATUS AND IMAGING METHOD THEREFOR

An imaging apparatus adjusts the polarization directions of irradiation beams (to a diffraction grating) corresponding to first and second beams respectively which have different polarization directions (for example, by adjusting a relative angle formed between light-emitting ends of respective polarization maintaining fibers) so that the spectral characteristics of the irradiation beams at the diffraction grating coincide with each other. Then, the imaging apparatus acquires a tomographic image indicating polarization information for a object based on beams (that come from the diffraction grating for splitting and diffracting a beam from the adjustment unit) corresponding to the first and second beams respectively which have different polarization directions. 1. An optical tomographic imaging apparatus comprising:a splitting unit configured to split a combined beam into first and second beams having different polarization directions, the combined beam being formed by combining a return beam from a object with a reference beam corresponding to the measuring beam, the object being irradiated with the measuring beam;an adjustment unit configured to adjust the polarization directions of irradiation beams to a diffraction grating corresponding to the first and second beams respectively so that the spectral characteristics of the irradiation beams at the diffraction grating coincide with each other; andthe diffraction grating configured to split and diffract beams from the adjustment unit corresponding to the first and second beams respectively;a detection unit configured to detect beams from the diffraction grating corresponding to the first and second beams respectively; andan acquisition unit configured to acquire a tomographic image indicating polarization information of the object based on outputs from the detection unit corresponding to the first and second beams respectively.2. The optical tomographic imaging apparatus according to claim 1 , wherein the adjustment ...

OPTICAL COHERENCE TOMOGRAPHY

An optical coherence tomography system comprising a light source (a) and a probe (e) that has a window at a front facing end. The window has an inner face (i) that has an anti-reflection surface and allows light from the source to pass through it, and an outer face (j) that reflects some of the light from the source and transmits some of the light to and from the sample (k). The reflected light acts as a reference. 1. An optical coherence tomography system comprising a light source and a probe that has a window at a front facing end , wherein the window has an inner face that has an anti-reflection surface and allows light from the source to pass through it , and an outer face that reflects some of the light from the source , the reflected light acting as a reference , and transmits some of the light to and from the sample.2. A system as claimed in wherein the anti-reflection surface is an anti-Newton surface.3. A system as claimed in wherein the outer face is treated to so that the reference signal is a scattered signal.4. A system as claimed in wherein the outer face is roughened claim 3 , thereby to cause the scattered signal.5. A system as claimed in wherein the scattered signal is small compared to the transmitted signal.6. A system as claimed in wherein the scattered light is less than 50% of the transmitted light.7. A system as claimed in wherein the probe includes one or more optical elements.8. A system as claimed in wherein the optical element comprises at least one focusing means.9. A system as claimed in wherein the focusing means comprises at least one lens.10. A system as claimed in comprising an optical fiber for coupling light into and out of the probe.11. A system as claimed in wherein the end of the fiber is shaped to focus light in the probe.12. A system as claimed in wherein the fiber is treated to avoid or reduce reflections from the end that is coupled with the probe.13. A system as claimed in wherein the fiber end is coated with an anti- ...

Optical imaging and mapping using propagation modes of light

Methods, systems, and devices are disclosed for implementing Doppler optical coherence tomography and microangiography imaging. In one aspect, a device for optically measuring a sample includes a swept light source to produce an input beam of coherent light for optically probing a target area of a sample, a waveguide to guide the input beam in two independent propagation modes, an optical probe to reflect a first propagation mode back to the waveguide and to direct a second propagation mode to the sample and to overlap the reflection from the sample with the first propagation mode, a differential delay controller to produce variable relative phase delays between the first propagation mode and the second propagation mode, a detection module to combine the first propagation mode and the second propagation mode and to extract information of the sample, and a processing unit to process the information to produce optical images.

METHOD AND DEVICE FOR HIGH RESOLUTION FULL FIELD INTERFERENCE MICROSCOPY

According to one aspect, the invention relates to a device () for three-dimensional imaging by full-field interferential microscopy of a volumic and scattering sample () comprising an emission source () for emitting an incident wave with low temporal coherence, an imaging interferometer () of variable magnification, allowing for the acquisition of at least one first and one second interferometric images resulting from the interference of a reference wave obtained by reflection of the incident wave on a reference mirror () and an object wave obtained by backscattering of the incident wave by a slice of the sample at a given depth of the sample, the at least two interferometric images having a phase difference obtained by varying the relative path difference between the object and reference arms of the interferometer, a processing unit () for processing said interferometric images making it possible to obtain a tomographic image of said slice of the sample, means for axially displacing the interferometer relative to the sample allowing for the acquisition of tomographic images for slices at different depths of the sample and means for varying the magnification of the imaging interferometer allowing for the acquisition of interferometric images of a slice of the sample for different magnification values. 1. A device for three-dimensional imaging by full-field interferential microscopy of a volumic and scattering sample , the device comprising:an emission source for emitting an incident wave with low temporal coherence; a reference arm comprising a reference mirror,', 'an object arm for receiving the scattering sample,', 'means for varying the relative path difference between the object and reference arms,', 'a multichannel acquisition device and an optical conjugation device with variable magnification for optically conjugating the sample and said multichannel device,', 'wherein the imaging interferometer allows for the acquisition of at least one first and one second ...

OPTICAL TOMOGRAPHIC IMAGING APPARATUS AND IMAGING METHOD THEREFOR

An optical tomographic imaging apparatus includes a first splitting unit configured to split a first beam and a second beam respectively into a reference beam and a measuring beam, an interference unit configured to acquire a first interference beam and a second interference beam by combining return beams being acquired by irradiating an inspection object with the respective measuring beams split by the splitting unit and the respectively corresponding reference beams, a second splitting unit configured to split the first interference beam into a third interference beam and a fourth interference beam, 1. An optical tomographic imaging apparatus comprising:a first splitting unit configured to split a first combined beam into a first beam and a second beam having different polarization directions, the first combined beam being formed by combining a return beam from an inspection object irradiated with a first measuring beam and a reference beam corresponding to the first measuring beam;a selection unit configured to select either a third beam or the second beam, the third beam being based on a second combined beam formed by combining a return beam from the inspection object irradiated with a second measuring beam and a reference beam corresponding to the second measuring beam;a first acquisition unit configured to acquire, if the second beam is selected by the selection unit, a tomographic image indicating polarization information of the inspection object based on the first beam and the second beam; anda second acquisition unit configured to acquire, if the third beam is selected by the selection unit, a tomographic image indicating a plurality of pieces of intensity information of the inspection object based on the first beam and the third beam.2. The optical tomographic imaging apparatus according to claim 1 , further comprising:a spectroscopic unit configured to disperse the first beam and the beam selected by the selection unit; andan irradiation unit configured ...

METHOD AND APPARATUS FOR THE REMOTE NONDESTRUCTIVE EVALUATION OF AN OBJECT

A method and apparatus for the remote nondestructive evaluation of an object such as a wind turbine blade involves applying mechanical and/or thermal stress to the object and then scanning the object using long-range thermographic and/or laser interferometric imaging. The laser interferometric imaging is preferably performed by a long range shearography camera capable of imaging deformation derivatives at long distances coupled with a blade stressing mechanism incorporating either thermal or internal blade pressurization for the purpose of detecting remotely and at high speed, changes in the structural integrity of an installed wind turbine blade. 1. A method of calibrating a shearography image , comprising:projecting two beams of structured light onto an object to form two dots having a known distance of separation;imaging the two dots with a shearography system; andcalibrating the shearography system using the known distance of separation.2. A method of calibrating a shearography image according to claim 1 , wherein the two beams of structured light are substantially parallel.3. A method of calibrating a shearography image according to claim 1 , wherein the step of calibrating the shearography system using the known distance of separation comprises determining a shearography image scale.4. A method of calibrating a shearography image according to claim 1 , further comprising determining a shear vector angle.5. A method of calibrating a shearography image according to claim 1 , further comprising determining a direction of shear.6. A method of calibrating a shearography image according to claim 1 , wherein the step of projecting the two beams of structured light onto an object is performed at a distance that is substantially within a range of about 50 feet to about 1500 feet.7. A method of calibrating a shearography image according to claim 6 , wherein the step of projecting the two beams of structured light onto an object is performed at a distance that is ...

OPTICAL PRESSURE SENSOR

Various embodiments include apparatus and methods of measuring pressure within pipes implemented in a well drilling operation. Methods and apparatus may include a single path optical interferometer having a sensing portion attachable to a location on a conduit and a dual path optical interferometer having a sensing portion attachable to the conduit, where the sensing portions are effectively collocated. Additional apparatus, systems, and methods are disclosed. 1. An apparatus comprising:a single path optical interferometer having a first sensing portion attachable to a location on a conduit; anda dual path optical interferometer having a second sensing portion attachable to the conduit essentially at the location of the first sensing portion on the conduit, the single path optical interferometer and the dual path optical interferometer arranged together to measure pressure within the conduit.2. The apparatus of claim 1 , wherein the single path optical interferometer includes a Sagnac interferometer to measure a direction of pressure change within the conduit.3. The apparatus of claim 2 , wherein the dual path optical interferometer includes a Michelson interferometer to measure an amount of the pressure change within the conduit.4. The apparatus of claim 2 , wherein the dual path optical interferometer includes a Mach-Zehnder interferometer to measure an amount of the pressure change within the conduit.5. The apparatus of claim 2 , wherein the Sagnac interferometer has a first optical source and the dual path optical interferometer has a second optical source.6. The apparatus of claim 2 , wherein the Sagnac interferometer and the dual path optical interferometer have a common optical source.7. The apparatus of claim 2 , wherein the first sensing portion and the second sensing portion are a common sensing portion.8. The apparatus of claim 7 , wherein the common sensing portion includes an optical fiber wound around the conduit.9. A method comprising:activating an ...

METHODS, SYSTEMS AND APPLICATIONS OF VARIABLE IMAGING DEPTH IN FOURIER DOMAIN OPTICAL COHERENCE TOMOGRAPHY

Systems, methods and applications for adjusting the imaging depth of a Fourier Domain optical coherence tomography system without impacting the axial resolution of the system are presented. One embodiment of the invention involves changing the sweep rate of a swept-source OCT system while maintaining the same data acquisition rate and spectral bandwidth of the source. Another embodiment involves changing the data acquisition rate of a SS-OCT system while maintaining the same sweep rate over the same spectral bandwidth. Several applications of variable imaging depth in the field of ophthalmic imaging are described. 1. A swept-source optical coherence tomography (SS-OCT) system generating images of the eye comprising:a light source for generating a probe beam wherein said source is swept over a spectral range at a sweep rate;optics for scanning the beam over a set of transverse locations across the eye;a detector for measuring light returned from the eye as a function of wavelength that acquires data at a data acquisition rate; anda processor for generating images of the eye based on the output of the detector over a sampling of wavelengths, said SS-OCT system capable of switching between imaging modes with different imaging depths by doing one or both of adjusting the sweep rate of the source or the data acquisition rate of the detector while the source is swept over substantially the same spectral range at each transverse location2. A system as recited in claim 1 , wherein the different imaging modes are used to image different portions of the eye.3. A system as recited in claim 2 , wherein the portions of the eye are selected from the retina claim 2 , the anterior chamber claim 2 , the choroid claim 2 , the cornea claim 2 , lens claim 2 , vitreous region claim 2 , and the optic disc.4. A system as recited in claim 1 , wherein the data acquisition rate is adjusted using a frequency multiplier or divider unit.5. A system as recited in claim 1 , wherein the light ...

LASER ULTRASONIC MEASUREMENT SYSTEM WITH MOVABLE BEAM DELIVERY

A laser ultrasonic measurement system includes a first and a second laser source configured to generate a first and a second laser beam, respectively. A movable mechanical link is arranged to transmit the first laser beam. The movable mechanical link is formed by a plurality of rigid sections interconnected by rotating joints. A robot is configured to support and control the movement of at least a section of the mechanical link to transmit the first laser beam to an object. An optical scanner is positioned proximate to the mechanical link. The optical scanner is configured to direct the first and second laser beams onto the object. An interferometer is optically coupled to the optical scanner. The interferometer is configured to receive reflected light from the object and in response generate an electrical signal. The first laser source is kinematically mounted in a housing assembly. 1. A laser ultrasonic measurement system , comprising:a first and a second laser source configured to generate a first and a second laser beam, respectively;a movable mechanical link having a first end and a second end arranged to optically transmit at least one of the laser beams from its laser source to the second end, the moveable mechanical link formed by a plurality of rigid sections interconnected by one or more rotating joints;a robot configured to support and control the movement of at least a section of the mechanical link to transmit at least one of the laser beams to an object;at least one optical element proximate to the second end of the moveable mechanical link, the at least one optical element configured to direct the first and second laser beams onto the object; andan interferometer optically coupled to the at least one optical element, the interferometer configured to receive reflected light from the object and to generate an electrical signal in response.2. The laser ultrasonic measurement system of claim 1 , wherein the at least one optical element comprises at least ...

Automatic calibration of fourier-domain optical coherence tomography systems

A method for calibrating a Fourier domain optical coherence tomography system includes receiving spectral data from an optical detector comprising a linear array of detector elements, each detector element having a position labeled n, wherein detected light was wavelength-dispersed across the linear array of detector elements; determining parameters of a preselected functional relationship between wave number, kn, corresponding to detector element n as a function of optical detector element n based on the spectral data; further receiving subsequent spectral data subsequent to the first-mentioned receiving, wherein detected light was wavelength-dispersed across the linear array of detector elements; converting the subsequent spectral data using the preselected functional relationship between wave number kn and optical detector element n to obtain converted spectral data; and performing an inverse Fourier transform of the converted spectral data to obtain a depth profile.

OPTICAL ELEMENT AND INTERFEROMETER

An optical element () is formed by bonding the faces of first to fourth triangular prisms () that form the apex angle, wherein bonding faces () of the first and second triangular prisms, bonding faces () of the second and third triangular prisms, bonding faces () of the third and fourth triangular prisms, and bonding faces () of the fourth and first triangular prisms are respectively bonded through an optical thin film. Each optical thin film allows the incident light to pass through, or reflects the incident light, depending on the polarization state. The optical element () splits an optical path at a first position of the optical thin film, and combines optical paths at a second position of the optical thin film. 1. An optical element comprising a plurality of optical thin films that split incident light into transmitted light and reflected light ,the optical element being formed by bonding faces of n (n is an integer equal to or larger than 3) polygonal prisms respectively through the plurality of optical thin films, andthe optical element splitting an optical path at a first position of one of the plurality of optical thin films, and combining the split optical paths at a second position of one of the plurality of optical thin films.2. The optical element according to claim 1 , wherein the plurality of optical thin films allow the incident light to pass through claim 1 , or reflect the incident light claim 1 , depending on a polarization state of the incident light.3. The optical element according to claim 2 ,wherein a quarter-wave plate or a half-wave plate is bonded to at least part of at least one face of a polygonal prism among the n polygonal prisms, andwherein the plurality of optical thin films allow light incident on the plurality of optical thin films after passing through the quarter-wave plate or the half-wave plate to pass through, or reflect the light.4. An interferometer comprising:a light source;an optical element that splits light emitted from ...

METHOD AND APPARATUS FOR PERFORMING OPTICAL IMAGING USING FREQUENCY-DOMAIN INTERFEROMETRY

An apparatus and method are provided. In particular, at least one first electro-magnetic radiation may be provided to a sample and at least one second electro-magnetic radiation can be provided to a non-reflective reference. A frequency of the first and/or second radiations varies over time. An interference is detected between at least one third radiation associated with the first radiation and at least one fourth radiation associated with the second radiation. Alternatively, the first electro-magnetic radiation and/or second electro-magnetic radiation have a spectrum which changes over time. The spectrum may contain multiple frequencies at a particular time. In addition, it is possible to detect the interference signal between the third radiation and the fourth radiation in a first polarization state. Further, it may be preferable to detect a further interference signal between the third and fourth radiations in a second polarization state which is different from the first polarization state. The first and/or second electro-magnetic radiations may have a spectrum whose mean frequency changes substantially continuously over time at a tuning speed that is greater than 100 Tera Hertz per millisecond. 193-. (canceled)94. An apparatus , comprising:at least one first arrangement configured to provide a radiation which includes at least one first electro-magnetic radiation directed to a sample and at least one second electro-magnetic radiation directed to a reference, wherein a frequency of the radiation provided by the at least one first arrangement varies over time; andat least one second arrangement configured to detect an interference between at least one third radiation associated with the at least one first radiation and at least one fourth radiation associated with the at least one second radiation to generate an electrical first signal,wherein the at least one second arrangement is configured to obtain a second signal associated with at least one phase of at least ...

Apparatus and Method for Detecting Pressure Signals

An apparatus for detecting data in a fluid pressure signal in a conduit comprises an optical fiber loop comprises a measurement section and a delay section wherein the measurement section is disposed substantially circumferentially around at least a portion of the conduit, and wherein the measurement section changes length in response to the fluid pressure signal in the conduit. A light source injects a first optical signal in a first direction into the measurement section and a second optical signal in a second direction opposite the first direction into the delay section. An optical detector senses an interference phase shift between the first optical signal and the second optical signal and outputs a first signal related thereto. 1. An apparatus for detecting data in a fluid pressure signal in a conduit comprising:an optical fiber loop comprising a measurement section and a delay section wherein the measurement section is disposed substantially circumferentially around at least a portion of the conduit and wherein the measurement section changes length in response to the fluid pressure signal in the conduit;a light source injecting a first optical signal in a first direction into the measurement section and a second optical signal in a second direction opposite the first direction into the delay section; andan optical detector to sense an interference phase shift between the first optical signal and the second optical signal and outputting a first signal related thereto.2. The apparatus of wherein the first signal is related to a time derivative of the fluid pressure signal in the conduit.3. The apparatus of wherein the measurement section and the delay section are sequentially disposed.4. The apparatus of further comprising a controller in data communication with the optical detector wherein the controller integrates the first signal with respect to time and generates an output signal substantially similar to the fluid pressure signal.5. The apparatus of wherein ...

ARRANGEMENT AND METHOD FOR INTERFEROMETRY

The invention relates to an arrangement for interferometry, including a light source for generating coherent radiation, a detector and a beam splitter for dividing the radiation generated by the light source. The radiation is divided into a sample arm in which a sample to be examined can be positioned and a reference arm. An optical reference element, which is partially transparent to the radiation, reflects a part of the radiation to the detector and behind which the sample to be examined can be positioned is disposed in the beam path of the sample arm. 112-. (canceled)14. Arrangement according to claim 13 , wherein the reference element comprises a plane surface facing the sample.15. Arrangement according to claim 13 , wherein the sample can be positioned in direct contact with the reference element.16. Arrangement according to claim 13 , wherein the reference element is wedge-shaped.17. Arrangement according to claim 13 , wherein the optical path length of the reference arm and/or the sample arm—in each case starting from the beam splitter—is variable.18. Arrangement according to claim 13 , wherein the optical path length of the reference arm and/or the sample arm can be adjusted such that the optical path lengths—in each case starting from the beam splitter—are identical.20. Method according to claim 19 , wherein the sample is positioned in direct contact with the reference element in the measurement.21. Method according to claim 19 , wherein the reference arm and the sample arm are adjusted for calibration such that their optical path lengths are identical. The present invention relates to an arrangement for interferometry according to the preamble of claim and to a corresponding method.In medical engineering, in the examination of biological samples, and in material science, interferometric measuring methods have meanwhile established themselves. They permit to obtain information on the internal structure of the respective sample in a non-invasive manner. To ...

Interferometric device with extrinsic optical fiber for measuring a physical parameter

An extrinsic optical fiber device () for measuring a physical parameter, includes: a light source (), of central wavelength λ, an optical fiber projecting (), a unit () for detecting an interferometric signal, the interferometric signal including the information about the physical parameter to be determined, elements () for modulating a signal emitted by the light source, elements () for calculating the physical parameter on the basis of the interferometric signal measured by the detection unit (). The modulated signal from the light source () includes an alternating component including a double frequency modulation generated by the modulation elements. The main application of this device is the measurement of the displacement of a target (). 11- Extrinsic optical fiber device () for measuring a physical parameter , comprising:{'b': '10', 'a light source (), of central wavelength λ, to generate a light beam in the direction of a target,'}{'b': '13', 'an optical fiber (), called the measurement fiber, to transport and guide the light beam towards a target, one extremity of said optical fiber, placed facing the target, forming with the target an optical cavity,'}{'b': '15', 'a means () for detecting an interferometric signal, said interferometric signal comprising the information about the physical parameter to be determined, and being generated by interference between a reference light beam and a measurement beam, said reference light beam corresponding to a fraction of the light beam from the light source that is reflected by the extremity of the fiber, and said measurement light beam corresponding to a fraction of the light beam from the light source that is reflected by the target and travels an optical path in the optical cavity whose variation is a function of the physical parameter to be determined,'}{'b': '17', 'means () for modulating a signal emitted by the light source,'}{'b': 18', '15, 'means () for calculating the physical parameter on the basis of the ...

DUAL WINDOW PROCESSING SCHEMES FOR SPECTROSCOPIC OPTICAL COHERENCE TOMOGRAPHY (OCT) AND FOURIER DOMAIN LOW COHERENCE INTERFEROMETRY

Current apparatuses and methods for analysis of spectroscopic optical coherence tomography (SOCT) signals suffer from an inherent tradeoff between time (depth) and frequency (wavelength) resolution. In one non-limiting embodiment, multiple or dual window (DW) apparatuses and methods for reconstructing time-frequency distributions (TFDs) that applies two windows that independently determine the optical and temporal resolution is provided. For example, optical resolution may relate to scattering information about a sample, and temporal resolution may be related to absorption or depth related information. The effectiveness of the apparatuses and methods is demonstrated in simulations and in processing of measured OCT signals that contain fields which vary in time and frequency. The DW technique may yield TFDs that maintain high spectral and temporal resolution and are free from the artifacts and limitations commonly observed with other processing methods. 1. A method of obtaining depth-resolved spectra of a sample for determining scattering and absorption characteristics within the sample , comprising:emitting a beam onto a splitter, wherein the splitter splits light from the beam to produce a reference beam, and an input beam to the sample;cross-correlating the reference beam with a sample beam returned from the sample as a result of the input beam by mixing the reference beam and the returned sample beam from the sample to yield a cross-correlated profile having optical, depth-resolved information about the returned sample beam; providing first one or more spectroscopic windows of the cross-correlated profile, each of the first one or more spectroscopic windows having a first width at a given center wavelength to obtain optical information about the sample for each given center wavelength;', 'applying a Fourier transform to the optical information about the sample to recover high resolution optical information about the sample at each given center wavelength ...

Information processing apparatus and method for fd-oct

An information processing apparatus for frequency domain optical coherence tomography comprises an image scanning unit that receives measurement data from an optical coherence tomography device, while moving a measurement point to the next adjacent point at each measurement time by controlling the optical coherence tomography device, and generates depth information based on the measurement data to produce a raw tomographic image. The apparatus includes a noise reduction unit that reduces noise from the raw tomographic image to produce a result tomographic image. The noise reduction unit reduces the noise from the raw tomographic image by subtracting the depth information generated by the image scanning unit at each measurement time from the depth information generated at another measurement time adjacent to said each measurement time.

Combination of mirror images to improve signal quality for contact lenses

A method and system to provide for increased signal intensity and improved signal quality in Fourier-domain optical coherence tomography (FDOCT) by capturing the real and virtual images of an object being imaged by FDOCT in sequence or consecutively.

OPTICAL COHERENCE TOMOGRAPHY APPARATUS AND OPERATING METHOD THEREOF

An optical coherence tomography apparatus includes a light source, a light coupling module, and an optical path difference generating module. The light source emits a coherent light. The light coupling module divides the coherent light into a first incident light and a second incident light. The first incident light is emitted to an item to be inspected and a first reflected light is generated. The second incident light is emitted to the optical path difference generating module, a second reflected light is generated according to the second incident light by the optical path difference generating module through changing the transparent/reflection properties of at least one optical devices of the optical path difference generating module, so that there is a optical path difference between the first reflected light and the second reflected light. 1. An optical coherence tomography (OCT) apparatus , comprising:a light source, for emitting a coherent light;a light coupling module, for dividing the coherent light into a first incident light and a second incident light, wherein the first incident light is emitted to an item to be inspected and a first reflected light is generated; andan optical path difference generating module comprising at least one optical device, when the second incident light is emitted to the optical path difference generating module, the optical path difference generating module changing the transparent/reflection properties of the at least one optical device to generate a second reflected light according to the second incident light to generate an optical path difference between the first reflected light and the second reflected light.2. The optical coherence tomography apparatus of claim 1 , wherein the at least one optical device is a plurality of liquid crystal units arranged in a multi-layer form claim 1 , the optical path difference generating module adjusts rotation angles of the plurality of liquid crystal units to change the transparent/ ...

Device for processing eye tissue by means of a pulsed laser beam

For processing eye tissue using a pulsed laser beam (L), an ophthalmological device includes a projection optical unit for the focused projection of the laser beam (L) into the eye tissue, and a scanner system upstream of the projection optical unit for the beam-deflecting scanning of the eye tissue with the laser beam (L) in a scanning movement (s′) performed over a scanning angle along a scanning line (s). The ophthalmological device includes a divergence modulator upstream of the scanner system for dynamically varying the divergence of the laser beam (L), whereby the scanning line (s) is tilted in a plane running through the optical axis of the projection optical unit and the scanning line(s). The tilting of the scanning line(s) enables a displacement—dependent on the scanning angle—of the focus of the laser pulses projected into the eye tissue without vertical displacement of the projection optical unit.

ARRANGEMENTS AND METHODS FOR PROVIDING MULTIMODALITY MICROSCOPIC IMAGING OF ONE OR MORE BIOLOGICAL STRUCTURES

Method and apparatus according to an exemplary embodiment of the present invention can be provided. For example, first data associated with a first signal received from at least one region of at least one sample can be provided based on a first modality, and second data associated with a second signal received from the at least one sample can be provided based on a second modality which is different from the first modality. Third data associated with a reference can be received. Further data can be generated based on the first, second and third data. In addition, third data associated with a second signal received from the at least one sample can be obtained. Each of the third data can be based on a further modality which is different from the first modality and the second modality, and the further data can be further determined based on the third data. Further, the first modality can be a spectral-encoded modality, and the second modality can be a non-spectral-encoding modality. 123-. (canceled)24. An apparatus comprising:at least one source first arrangement configured to provide an electro-magnetic radiation; andat least one second arrangement configured to provide (i) first data associated with a first signal received from at least one region of at least one sample based on a first modality, (ii) second data associated with a second signal received from the at least one sample based on a second modality which is different from the first modality, and (iii) at least one third data associated with a third signal received from the at least one sample, wherein each of the at least one third data is based on a third modality which is different from at least one of the first modality or the second modality,wherein at least two of the first, second and third signals are caused by the electro-magnetic radiation provided by the at least one first arrangement.25. The apparatus according to claim 24 , further comprising at least one third arrangement which is configured to ...

OPTICAL SCANNING AND IMAGING SYSTEMS BASED ON DUAL PULSED LASER SYSTEMS

The invention relates to scanning pulsed laser systems for optical imaging. Coherent dual scanning laser systems (CDSL) are disclosed and some applications thereof. Various alternatives for implementation are illustrated, including highly integrated configurations. In at least one embodiment a coherent dual scanning laser system (CDSL) includes two passively modelocked fiber oscillators. The oscillators are configured to operate at slightly different repetition rates, such that a difference δfin repetition rates is small compared to the values fand fof the repetition rates of the oscillators. The CDSL system also includes a non-linear frequency conversion section optically connected to each oscillator. The section includes a non-linear optical element generating a frequency converted spectral output having a spectral bandwidth and a frequency comb comprising harmonics of the oscillator repetition rates. A CDSL may be arranged in an imaging system for one or more of optical imaging, microscopy, micro-spectroscopy and/or THz imaging. 1. A coherent dual scanning laser system , comprising:{'sub': r', 'r1', 'r2, 'first and second passively modelocked fiber oscillators, each of said first and second oscillators arranged with intra-cavity dispersion compensation and to operate at slightly different repetition rates, such that a difference Δfin repetition rates is small compared to the values fand fof the respective repetition rates of said first and second oscillators, said first and second oscillators producing respective first and second pulse trains;'}a first optical splitter to spatially split and direct said first pulse train along a plurality of optical paths, including a first frequency conversion path; a first non-linear frequency converter disposed downstream from said first passively modelocked fiber oscillator and optically connected to said first passively modelocked fiber oscillator, said first non-linear frequency converter disposed in said first frequency ...

Film thickness monitor

A measurement unit comprising a light source and a photodetector may be formed in a cavity in a substrate. The light source produces light that impinges a material layer and is reflected back to the photodetector. Through methods such as interferometry and ellipsometry, the thickness of the material layer may be calculated from the light intensity data measured by the photodetector. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

LOW COHERENCE INTERFEROMETRY WITH SCAN ERROR CORRECTION

A system includes an interference microscope having one or more optical elements arranged to image a test object to an image plane by combining test light from the test object with reference light from a reference object to form an interference pattern at the image plane, wherein the test and reference light are derived from a common broadband light source. The system includes a scanning stage configured to scan an optical path difference (OPD) between the test and reference light, a multi-element detector positioned at the image plane and configured to record the interference pattern for each of a series of OPD increments and to generate multiple interferometry signals each having a fringe carrier frequency indicative of changes in the OPD as the OPD is scanned, where there is phase diversity among the interferometry signals, and an electronic processor coupled to the multi-element detector and scanning stage and configured to process the interference signals based on the phase diversity to determine information about the OPD increments having sensitivity to perturbations to the OPD increments at frequencies greater than the fringe carrier frequency. 1. A system comprising:an interference microscope comprising one or more optical elements arranged to image a test object to an image plane by combining test light from the test object with reference light from a reference object to form an interference pattern at the image plane, wherein the test and reference light are derived from a common broadband light source;a scanning stage configured to scan an optical path difference (OPD) between the test and reference light;a multi-element detector positioned at the image plane and configured to record the interference pattern for each of a series of OPD increments and to generate multiple interferometry signals each having a fringe carrier frequency indicative of changes in the OPD as the OPD is scanned, where there is phase diversity among the interferometry signals; ...

MEASURING APPARATUS INCLUDING MULTI-WAVELENGTH INTERFEROMETER

A measuring apparatus for measuring a position or a shape of a surface to be inspected includes a multi-wavelength interferometer and a control unit. The multi-wavelength interferometer includes an optical system that causes light to be inspected, which enters the surface to be inspected and is reflected by the surface to be inspected, and reference light to interfere with each other, a spectroscopic unit that divides interference light between the light to be inspected and the reference light into each wavelength, and a detector that detects the interference light and is provided for each divided interference light and an optical member that can adjust a position of a light guide portion that guides light from the spectroscopic unit to the detector. The control unit controls the optical member by using information related to inclination of the surface to be inspected to adjust the position of the light guide portion. 1. A measuring apparatus for measuring a position or a shape of a surface to be inspected , the measuring apparatus comprising:a multi-wavelength interferometer configured to use a plurality of light fluxes whose wavelengths are different from each other; anda control unit configured to obtain a position or a shape of the surface to be inspected by using a signal of interference light detected by the multi-wavelength interferometer,wherein the multi-wavelength interferometer includesan optical system configured to cause light to be inspected, which enters the surface to be inspected and is reflected by the surface to be inspected, and reference light to interfere with each other,a spectroscopic unit configured to divide interference light between the light to be inspected and the reference light into each wavelength,a detector configured to detect the interference light and provided for each divided interference light, andan optical member configured to be able to adjust a position of a light guide portion that guides light from the spectroscopic unit ...

APPARATUS, METHOD, AND TALBOT INTERFEROMETER FOR CALCULATING ABERRATION OF TEST OPTICAL SYSTEM

A calculation apparatus acquires image data of interference fringes detected by using a Talbot interferometer including a diffraction grating and a detector, retrieves a first wavefront by using the image data of the interference fringe, sets a value of a second wavefront incident on the diffraction grating, calculates an interference fringe image of a plurality of the diffracted light beams through simulation, and retrieves a third wavefront by using the calculated interference fringe image, wherein the third wavefront is retrieved by changing a position of the diffraction grating in a plane perpendicular to an optical axis of the Talbot interferometer, and aberration of a test optical system is calculated by reducing an error included in the first wavefront by using the second wavefront and the third wavefront. 1. A calculation apparatus for calculating aberration of a test optical system , comprising:an acquisition unit which acquires image data of interference fringes detected by using a Talbot interferometer including a diffraction grating which divides a light beam incident on the test optical system into a plurality of diffracted light beams and a detector which detects the interference fringes of the plurality of the diffracted light beams; andan operation unit which retrieves a first wavefront by using the image data of the interference fringes and which sets a value of a second wavefront incident on the diffraction grating, calculates an interference fringe image of the plurality of the diffracted light beams through simulation, and retrieves a third wavefront by using the calculated interference fringe image,wherein the operation unit retrieves the third wavefront by changing a position of the diffraction grating in a plane perpendicular to an optical axis of the Talbot interferometer to match a phase of a carrier frequency component of the detected interference fringes with a phase of a carrier frequency component of the interference fringe image ...

METHOD FOR GENERATING INFORMATION SIGNAL

A signal generation method for generating an information signal F(b) by performing a Fourier transform on a signal f(a) includes the following steps: detecting the maximum peak intensity of the information signal F(b); calculating an amplitude, a phase, and a frequency of the signal f(a) corresponding to the maximum peak intensity; generating a signal by causing the signal f(a) corresponding to the maximum peak intensity to extend along an ‘a’ axis on the basis of information about the amplitude, the phase, and the frequency of the signal f(a); generating an extrapolation signal by extracting a signal in a region smaller than a1 and a signal in a region larger than a2 from the signal, where a1 Подробнее

Spatial Light Interference Tomography

Methods and a computer readable medium for deriving a quantitative phase contrast tomographic image of a specimen. The specimen is illuminated and a focus of the illuminating light is scanned to a plurality of depths within the specimen. Light transmitted through the specimen is spatially Fourier transformed at each of the plurality of depths to form a spatially transformed image, and at least one of the phase and amplitude of a plurality of spatial frequency components of the spatially transformed image is spatially modulated. An intensity image of the specimen plane as modulated with respect to spatial frequency components is detected and deconvolved at a plurality of spatially modulated instances to obtain a three-dimensional phase representation of the specimen at each of the plurality of distances relative to a fiducial plane. 1. A method for deriving a quantitative phase contrast tomographic image of a specimen , the method comprising steps of:a. illuminating the specimen with illuminating light characterized by a coherence length substantially shorter than a dimension of a feature of the specimen to be resolved;b. scanning a focus of the illuminating light to a plurality of depths within the specimen;c. spatially Fourier transforming light transmitted through the specimen at each of the plurality of depths to form a spatially Fourier transformed image;d. spatially modulating at least one of the phase and amplitude of a plurality of spatial frequency components of the spatially Fourier transformed image;e. detecting an intensity image of the specimen plane as modulated with respect to spatial frequency components and as interfered with an unscattered component of the illuminating light;f. deconvolving the intensity image at a plurality of spatially modulated instances to obtain a three-dimensional phase representation of the specimen at each of the plurality of distances relative to a fiducial plane; andg. further deconvolving a modeled point spread function ...

Optical coherence tomography using active mode-locking fiber laser

Discloses is an optical coherence tomography (OCT) which uses an active mode-locking fiber laser in order to obtain image information of a sample. An imaging device in accordance with an embodiment comprises: a light source unit; a light separation unit; a reference unit; a diagnostic unit; a light coupling unit; and a signal processing unit. The imaging device removes a high-priced variable filter which has mechanical restrictions by directly delivering a modulation signal to a light source unit, so it can overcome mechanical restrictions and reduce costs.

Optical coherence tomography apparatus and method

An OCT apparatus includes, in addition to a first light source that changes a wavelength of light that is emitted, a second light source that emits light having a particular wavelength. The OCT apparatus is formed so that, when light having the particular wavelength is emitted from the first light source, the light emitted from the second light source is detected by a second optical detector.

OPTICAL PROBE AND OPTICAL COHERENCE TOMOGRAPHY APPARATUS INCLUDING THE SAME

An optical probe for irradiating light onto a subject includes an optical path control unit configured to receive light from outside the optical probe, and change a path of the light within the optical probe; an optical path length control element configured to receive the light having the changed path from the optical path control unit, and change an optical path length of the light as the optical path control unit changes the path of the light; and an optical output unit configured to receive the light having the changed optical path length from the optical path length control element, and output the light. 1. An optical probe for irradiating light onto a subject , the optical probe comprising:an optical path control unit configured to receive light from outside the optical probe, and change a path of the light within the optical probe;an optical path length control element configured to receive the light having the changed path from the optical path control unit, and change an optical path length of the light as the optical path control unit changes the path of the light; andan optical output unit configured to receive the light having the changed optical path length from the optical path length control element, and output the light.2. The optical probe of claim 1 , wherein the optical output unit is further configured to irradiate the light output from the optical output unit onto a subject;the optical path control unit is further configured to change the path of the light to repeatedly move a point where the light output from the optical output unit is irradiated onto the subject by a predetermined distance in a predetermined direction; andthe optical path length control element is further configured to uniformly change the optical path length each time the point where the light is irradiated onto the subject moves.3. The optical probe of claim 1 , wherein the optical path length control element is further configured to transmit the light having the changed ...

INTERFEROMETER AND METHOD FOR CONTROLLING THE COALESCENCE OF A PAIR OF PHOTONS

An interferometer for controlling the coalescence of a pair of photons, including: an optical source, which generates a first and a second pump pulse coherent with each other and shifted in time by a delay; and a first interferometric stage, which receives the first pump pulse and generates an antisymmetric state with two coalescent photons (1/√{square root over (2)}(|2,0−|0,2)). The interferometer also includes a second interferometric stage, which receives the second pump pulse and generates a symmetric state with two coalescent photons (1/√{square root over (2)}·(|2,0+|0,2)), the first and the second interferometric stages being connected in a manner such that the interferometer outputs a final state equal to a weighted sum of the antisymmetric state and of the symmetric state (1/√{square root over (2)}·(|2,0+|0,2)+e·1/√{square root over (2)}·(|2,0−|0,2)), the weights of the sum being a function of the delay. 1. An interferometer for controlling the coalescence of a pair of photons , comprising:an optical source configured to generate a first pump pulse and a second pump pulse coherent with each other and shifted in time by a delay;{'sub': 1', '2', '1', '2, 'img': [{'@id': 'CUSTOM-CHARACTER-00037', '@he': '3.56mm', '@wi': '0.68mm', '@file': 'US20130176573A1-20130711-P00002.TIF', '@alt': 'custom-character', '@img-content': 'character', '@img-format': 'tif'}, {'@id': 'CUSTOM-CHARACTER-00038', '@he': '3.56mm', '@wi': '0.68mm', '@file': 'US20130176573A1-20130711-P00002.TIF', '@alt': 'custom-character', '@img-content': 'character', '@img-format': 'tif'}], 'first interferometric means configured to receive the first pump pulse and generate an antisymmetric state with two coalescent photons (1/√{square root over (2)}(|2,0−|0,2));'}{'sub': 1', '2', '1', '2, 'img': [{'@id': 'CUSTOM-CHARACTER-00039', '@he': '3.56mm', '@wi': '0.68mm', '@file': 'US20130176573A1-20130711-P00002.TIF', '@alt': 'custom-character', '@img-content': 'character', '@img-format': 'tif'}, {'@id': ' ...

Image sensor, attitude detector, contact probe, and multi-sensing probe

An image sensor for fringe images of interference fringes and the like in which the optical system has a simpler configuration than that of the conventional line image sensor, and faster detection becomes possible includes a light receiving plane on which two or more straight rows of pixels are disposed, and captures images of regular fringes generated from light reflected from an irradiated body in accordance with the amount of light received by each pixel; among the rows of pixels, at least two rows of pixels are disposed at right angles to each other, and acquires images of linear fringes crossing almost at right angles in two directions among the fringe projected onto the light receiving plane.

APPARATUS AND METHOD OF GENERATING A TOMOGRAPHIC IMAGE

A method and an apparatus for generating a tomographic image are provided. The method for generating a tomographic image may involve: detecting a principal frequency region corresponding to a portion of a frequency data corresponding to a tomographic image, determining a plurality of sub frequency regions within the principal frequency region, and generating, by a processor, the tomographic image by synthesizing data of the plurality of sub frequency regions. 1. An image generating method comprising:detecting a principal frequency region corresponding to a portion of a frequency data corresponding to a tomographic image;determining a plurality of sub frequency regions within the principal frequency region; andgenerating, by a processor, the tomographic image by synthesizing data of the plurality of sub frequency regions.2. The image generating method of claim 1 , further comprising displaying the generated tomographic image on a display unit.3. The image generating method of claim 1 , wherein the generating of the tomographic image comprises:performing frequency inverse-transformation on the data of each of the plurality of sub frequency regions;forming a plurality of sub images by transforming data obtained from the frequency inverse-transformation into data of a frequency region with respect to a depth direction of a target; andgenerating the tomographic image of the target by synthesizing the plurality of sub images.4. The image generating method of claim 3 , wherein the generating of the tomographic image comprises calculating an average of pixel data of the sub images.5. The image generating method of claim 1 , wherein the detecting of the principal frequency region comprises selecting a region of the frequency data based on a waveform of the frequency data.6. The image generating method of claim 1 , wherein the data of the frequency region is distributed substantially symmetrically about a central frequency claim 1 , and the detecting of the principal ...

IMAGING APPARATUS USING TALBOT INTERFERENCE AND ADJUSTING METHOD FOR IMAGING APPARATUS

An imaging apparatus includes a diffraction grating which diffracts electromagnetic waves from an electromagnetic wave source, a shield grating which shields a part of the electromagnetic waves diffracted by the diffraction grating, a detector which detects an intensity distribution of the electromagnetic waves through the shield grating, and an adjusting unit which adjusts the attitude of at least one of the diffraction grating and the shield grating on the basis of the detection result by the detector, wherein the adjusting unit divides the intensity distribution detected by the detector into a plurality of regions and adjusts the attitude of at least one of the diffraction grating and the shield grating on the basis of the intensity distributions of the plurality of regions. 1. An imaging apparatus comprising:a diffraction grating which diffracts electromagnetic waves from an electromagnetic wave source;a shield grating which shields a part of the electromagnetic waves diffracted by the diffraction grating;a detector which detects an intensity distribution of the electromagnetic waves through the shield grating; andan adjusting unit which adjusts the attitude of at least one of the diffraction grating and the shield grating on the basis of the detection result by the detector,wherein the adjusting unit:divides the intensity distribution detected by the detector into a plurality of regions; andadjusts the attitude of at least one of the diffraction grating and the shield grating on the basis of the intensity distributions of the plurality of regions.2. The imaging apparatus according to claim 1 , whereinthe adjusting unit performs Fourier transform on the intensity distributions in the divided plurality of regions and thus calculates the intensity information on the spectra corresponding to the carrier frequencies; andadjusts the attitude of at least one of the diffraction grating and the shield grating on the basis of the intensity distributions of the spectra ...

User interface for efficiently displaying relevant oct imaging data

The present invention is an OCT imaging system user interface for efficiently providing relevant image displays to the user. These displays are used during image acquisition to align patients and verify acquisition image quality. During image analysis, these displays indicate positional relationships between displayed data images, automatically display suspicious analysis, automatically display diagnostic data, simultaneously display similar data from multiple visits, improve access to archived data, and provide other improvements for efficient data presentation of relevant information.

PHOTOGRAPHING APPARATUS AND PHOTOGRAPHING METHOD

In order to place a coherence gate as close as possible to a object, provided is a tomographic image photographing apparatus including: a moving unit for moving the coherence gate corresponding to a difference between an optical path length of measuring light and an optical path length of reference light; and a control unit for controlling the moving unit so as to further move the coherence gate from a second position based on first combined light and second combined light of the object, which are respectively acquired at a first position of the coherence gate and the second position at which the coherence gate is placed after being moved from the first position to the object side by the moving unit. 1. A photographing apparatus for photographing a tomographic image of a object based on combined light of return light from the object irradiated with measuring light and reference light corresponding to the measuring light , the photographing apparatus comprising:a moving unit configured to move a coherence gate corresponding to a difference between an optical path length of the measuring light and an optical path length of the reference light; anda control unit configured to control the moving unit so as to move the coherence gate from a second position based on first combined light and second combined light of the object, which are respectively acquired at a first position of the coherence gate and the second position at which the coherence gate is placed after being moved from the first position to the object side by the moving unit.2. A photographing apparatus according to claim 1 , further comprising a movement direction acquiring unit configured to acquire a movement direction of the coherence gate based on the first combined light and the second combined light of the object claim 1 , which are respectively acquired at the first position and the second position claim 1 ,wherein the control unit controls the moving unit so as to move the coherence gate in the ...

SYSTEM AND METHOD FOR CALIBRATED SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY AND LOW COHERENCE INTERFEROMETRY

Systems and methods for enhancing spectral domain optical coherence tomography (OCT] are provided. In particular, a system and method for calibration of spectral interference signals using an acquired calibration signal are provided. The calibration signal may be logarithmically amplified to further improve the accuracy of the calibration. From the calibration signal, a series of more accurate calibration data are calculated. An acquired spectral interference signal is calibrated using these calibration data. Moreover, systems that include logarithmic amplification of the spectral interference signal and variable band-pass filtering of the spectral interference signal are provided. Such systems increase the dynamic range and visualization capabilities relative to conventional spectral domain OCT systems. 1. An optical coherence tomography system comprising:a light source configured to produce light to illuminate a sample with the sample light;at least one optical path configured to receive at least one of reference light and sample light from the light source and to illuminate a sample with the received sample light;a detector in optical communication with the at least one optical path and configured to receive the reference and sample light; a) receive a signal from the detector;', 'b) determine, from the received signal, an interference signal related to the reference light and the sample light;', 'c) receive a calibration signal from the light source;', 'd) identify at least one of a series of extrema and a series of crossing values in the received calibration signal;', 'e) identify at least one of a series of calibration extrema and a series of calibration crossing values from the received calibration signal and the identified at least one of series of extrema and series of crossing values by performing an interpolation;', 'f) calibrate the interference signal using the identified at least one of a series of calibration extrema and series of calibration crossing ...

Swept source optical coherence tomography (OCT) method and system

A method and apparatus are provided for a swept source optical coherence tomography (OCT) system utilizing a fast scanning mechanism in the sample arm and a slowly swept light source. The position data is collected rapidly while the wavelength of the source is swept slowly. The system reduces the sweep speed requirements of the light source enabling higher power, greater imaging range, and linear sweeps of the source frequency. The OCT components (or most of them) may be implemented within a hand held imaging probe. In operation, a triangulation scan may be used to orient the imaging probe with respect to a fixed coordinate system; preferably, OCT data captured by the device is then transformed to that same orientation with respect to the fixed coordinate system to improve the scanning results. 1. A method of scanning an object using a light source , comprising:(a) triangulation scanning the object to produce a mesh in a fixed coordinate system;(b) at each of one or more scan locations overlapping with the mesh, performing a scan in triangulation mode, and a scan in optical coherence tomography (OCT) mode;(c) computing, using software executing in a hardware element, a transformation matrix that registers the scan in triangulation mode with the mesh;(d) applying the transformation matrix to data collected from the scan in OCT mode to generate transformed OCT data; and(e) merging the transformed OCT data into a mesh that is in the fixed coordinate system.2. The method as described in wherein the scan in OCT mode comprises at least first and second lateral scans over an area to be imaged as a wavelength of the light source is swept.3. The method as described in wherein during a first lateral scan the wavelength of the light source has a first claim 2 , substantially constant value claim 2 , wherein during a second lateral scan the wavelength of the light source has a second claim 2 , substantially constant value claim 2 , where the first and second values differ. This ...

OPTICAL TOMOGRAPHIC IMAGING SYSTEM AND OPTICAL TOMOGRAPHIC IMAGING METHOD

An optical tomographic imaging method according to one aspect of the present invention is a method of: splitting light emitted from a wavelength sweep light source into measuring light and reference light; radiating the measuring light onto a measuring subject; combining reflection light from the measuring subject with the reference light; detecting interfered light obtained by combining the reflection light with the reference light as an interference signal; and Fourier-transforming the interference signal to acquire a tomographic image of the measuring subject, and includes steps of: generating tomographic data of the measuring subject based on the interference signal; generating surface data of the measuring subject based on the interference signal; constructing a tomographic image that is based on the generated tomographic data; constructing a surface image that is based on the outputted surface data; and generating a display image from the tomographic image and the surface image. 1. An optical tomographic imaging system configured to split light emitted from a wavelength sweep light source into measuring light and reference light , configured to radiate the measuring light onto a measuring subject , configured to combine reflection light from the measuring subject with the reference light , configured to detect interfered light obtained by combining the reflection light with the reference light as an interference signal , and configured to Fourier-transform the interference signal to acquire a tomographic image of the measuring subject , the optical tomographic imaging system comprising:a tomographic data generating unit configured to generate tomographic data of the measuring subject based on the interference signal;a surface data generating unit configured to carry out processing in parallel with the tomographic data generating unit and configured to generate surface data of the measuring subject based on the interference signal;a tomographic image ...

Method for Reducing Wafer Shape and Thickness Measurement Errors Resulted From Cavity Shape Changes

Methods and systems for reducing wafer shape and thickness measurement errors resulted from cavity shape changes are disclosed. Cavity calibration process is performed immediately before the wafer measurement. Calibrating the cavity characteristics every time the method is executed reduces wafer shape and thickness measurement errors resulted from cavity shape changes. Additionally or alternatively, a polynomial fitting process utilizing a polynomial of at least a second order is utilized for cavity tilt estimation. High order cavity shape information generated using high order polynomials takes into consideration cavity shape changes due to temperature variations, stress or the like, effectively increases accuracy of the wafer shape and thickness information computed. 1. A method for measuring the thickness variation and shape of wafers , the method comprising:calibrating characteristics of a cavity formed between reference flats in two opposing interferometer channels;placing a wafer in the cavity immediately upon completion of calibrating the cavity characteristics;synchronizing the interferograms in the two interferometer channels by supplying the light from a single wavelength tunable laser light source, the output beam of which is split by a beam splitter to propagate to both interferometer channels;measuring the cavity characteristics of the reference flats forming the cavity providing an oversized field of view of the wafer in the cavity for obtaining a difference map in the cavity areas outside of the wafer and measuring the cavity tilt of the reference flats; anddetermining the thickness variations of the wafer based on the cavity characteristic measurements and the cavity tilt of the reference flats,wherein the cavity characteristics are calibrated every time the method is executed to reduce wafer shape and thickness measurement errors resulted from cavity shape changes.2. The method of claim 1 , wherein the step of measuring the cavity tilt includes a ...

Apparatus And Method Of Measuring Roughness And Other Parameters Of A Structure

Systems and methods are presented to enhance and isolate residual signals indicative of the speckle field based on measurements taken by optically based metrology systems. Structural irregularities such as roughness and topographical errors give rise to light scattered outside of the specularly reflected component of the diffracted light. The scattered light interferes constructively or destructively with the specular component in a high numerical aperture illumination and detection system to form a speckle field. Various methods of determining residual signals indicative of the speckle field are presented. Furthermore, various methods of determining structural irregularities based on analysis of the residual signals are presented. In various embodiments, illumination with a high degree of spatial coherence is provided over any of a wide range of angles of incidence, multiple polarization channels, and multiple wavelength channels. In addition, diffracted light is collected over a wide range of angles of detection.

METHOD FOR OBSERVING PROTEIN CRYSTAL

Provided are a method for observing protein crystal, wherein the growth process of the protein crystals is nondestructively and three-dimensionally monitored on a real-time basis and the growth of the crystals is controlled at a high accuracy to thereby enable the formation of single crystals having good qualities, which comprises observing the protein crystals, said protein crystals having been produced by a crystallization method using a gel, by an OCT measurement using light emitted from an ultrawideband light source; 1. A method for observing protein crystal for producing a good quality crystal of a protein , wherein protein crystal produced by a crystallization method using a gel is observed by OCT measurement measuring light emitting from an ultra-wideband light source and an interfering light generated from a scattering light of the emitting light.2. The method for observing protein crystal according to claim 1 , wherein the above-described ultra-wideband light source is an ultra-wideband supercontinuum light source.3. The method for observing protein crystal according to claim 2 , wherein the center wavelength of light emitting from the above-described ultra-wideband supercontinuum light source is of 0.8 μm band.4. The method for observing protein crystal according to claim 1 , wherein the above-described observation for protein crystal is observation by in-situ measurement.5. A method for evaluating protein crystal claim 1 , wherein evaluation of protein crystal is carried out using the method for observing protein crystal according to .6. A method for distinguishing a protein crystal and a salt claim 1 , wherein separation of a protein crystal and a salt is carried out using the method for observing protein crystal according to .7. A method for separating a protein crystal and a salt for producing quality crystal of a comprisinga gel liquid production step of gelling a material to be measured containing a protein and a salt to produce gel liquid,a protein ...

SYSTEMS, METHODS, APPARATUS AND COMPUTER-ACCESSIBLE-MEDIUM FOR PROVIDING POLARIZATION-MODE DISPERSION COMPENSATION IN OPTICAL COHERENCE TOMOGRAPHY

Exemplary systems, apparatus, methods and computer-accessible medium for generating information regarding at least one sample can be provided. For example, it is possible to receiving first data which is based on at least one first radiation provided to the sample(s) and at least one second radiation provided from the sample(s) that is/are associated with the first radiation(s) It is also possible to generate second data by reducing the influence of first optical effects induced on the first radiation(s) prior to reaching the sample(s), and second optical effects induced on the second radiation(s) after leaving the sample(s). 1. An apparatus for generating information regarding at least one sample , comprising: receive first data, second data, third data and fourth data, wherein', 'i. the first data is associated with a first radiation provided to the at least one sample, a second radiation from the at least one sample, and at least one further radiation provided from the at least one sample or a reference,', 'ii. the second data is associated with a third radiation provided to the at least one sample, the second radiation, and the at least one further radiation,', 'iii. the third data is associated with the first radiation, a fourth radiation from the at least one sample, and the at least one further radiation,', 'iii. the fourth data is associated with the third radiation, the fourth radiation from the at least one sample, and the at least one further radiation,', 'iv. wherein each of the first and third radiations and the second and fourth radiations have polarizations states are different from one another; and, 'at least one first arrangement which is configured toa second arrangement which is configured to generate fifth data by combining at least two of the first, second, third and fourth data, wherein the combination reduces the influence of optical effects induced on the first and third radiations prior to reaching the at least one sample, and optical ...

IMAGE PROCESSING APPARATUS AND IMAGE PROCESSING METHOD

An image processing apparatus includes a planar image acquisition unit configured to acquire a planar image of a subject, a tomographic image acquisition unit configured to acquire a tomographic image indicating a polarization state of the subject, and a display control unit configured to cause a display unit to display the planar image and the tomographic image indicating the polarization state side by side. 1. An image processing apparatus comprising:a planar image acquisition unit configured to acquire a planar image of a subject;a tomographic image acquisition unit configured to acquire a polarization-sensitive tomographic image of the subject; anda display control unit configured to cause a display unit to display the planar image and the polarization-sensitive tomographic image side by side.2. The image processing apparatus according to claim 1 , wherein the display control unit causes the display unit to display claim 1 , on the planar image claim 1 , an acquisition position of the polarization-sensitive tomographic image in the subject.3. The image processing apparatus according to claim 1 , further comprising an analysis unit configured to analyze the polarization-sensitive tomographic image claim 1 ,wherein the display control unit causes the display unit to display a display form indicating the analysis result along with the planar image and the polarization-sensitive tomographic image.4. The image processing apparatus according to claim 3 , wherein the subject includes a subject's eye claim 3 , andwherein the analysis unit performs segmentation of layers in a retina of the subject's eye included in the polarization-sensitive tomographic image.5. The image processing apparatus according to claim 4 , wherein the display control unit causes the display unit to display a display form indicating layer thicknesses of the layers in the retina.6. The image processing apparatus according to claim 1 , wherein the polarization-sensitive tomographic image includes a ...