EXTENDED CAVITY SEMICONDUCTOR LASER DEVICE WITH INCREASED INTENSITY

The present invention relates to an extended cavity semiconductor laser device comprising an array of at least two semiconductor gain elements (20, 21), each of said semiconductor gain elements (20, 21) comprising a layer structure (1) forming a first end mirror (2) and an active medium (3). A coupling component (22) inside of the device combines fundamental laser radiation emitted by said array of semiconductor gain elements (20, 21) to a single combined laser beam (25). A second end mirror (23) reflects at least part of said single combined laser beam (23) back to said coupling component (22) to form extended cavities with the first end mirrors (2). Due to this coherent coupling of several extended cavity semiconductor lasers a single beam of the fundamental radiation is generated with increased intensity, good beam profile and narrow spectral band width. This beam of increased intensity is much better suited for frequency conversion via upconversion or via second harmonic generation ...

Laser Projection System Based on a Luminescent Screen

The present invention relates to a laser projection system consisting of at least one first laser light source ( 1 ), a projection screen ( 7 ) and a spatial light modulator ( 6 ) for projecting a laser beam of said laser light source ( 1 ) to form an image on said projection screen ( 7 ). The projection screen ( 7 ) comprises a luminescent layer ( 9 ) which upon excitation by said laser beam emits blue light. To this end, the luminescent layer ( 9 ) contains MSi 6-a Al a N 8-a O x+a :Eu 2+ (with M=Sr, Ba, Ca; 0≦x≦1; 0≦a≦1) as a luminescent material. With this material laser light of a laser diode emitting in the wavelength region of 405 nm can be converted to blue light of 450 nm with high efficiency. The proposed projection system, therefore, is suitable for RGB projection using laser diodes as laser light sources.

Vertical cavity surface emitting laser device with integrated tunnel junction

A Vertical Cavity Surface Emitting Laser (VCSEL) (100) comprises first and second electrical contacts (105, 150), an active layer (120), a resonator, and first and second distributed Bragg reflectors (DBR) (115, 125). The first DBR (115) or the second DBR (125) comprises a first part (115-1, 125-1) with at least one pair of layers with different refractive indices and a second part (115-2, 125-2) with at least one pair of layers with different refractive indices. The first and second parts (115-1, 125-1), (115-2, 125-2) are characterized by different conductivity types. A tunnel junction (130) is arranged between the first part and the second part. The first and second electrical contacts (105, 150) are arranged to electrically pump the resonator wherein the tunnel junction (130) is reversely biased. When the first DBR comprises the first part and the second part with respect to the total thickness of the first part and second part of the DBR is between 0.1-0.8. Alternatively, when then ...

METHOD OF SWITCHING LASER EMISSION OF A SOLID STATE LASER BETWEEN DIFFERENT EMISSION WAVELENGTHS AND CORRESPONDING SOLID STATE LASER DEVICE

The present invention relates to a method of switching laser emission of a solid state laser between different emission wavelengths, said different emission wavelengths being based on different electronic transitions in a solid state laser medium ( 3 ) of the solid state laser. The at least two end mirrors ( 1, 2 ) of the solid state laser are designed to allow lasing of the laser at the different emission wavelengths and coupling out of the different emission wavelengths at one end mirror ( 2 ) of the laser cavity. The switching of the laser emission is achieved by switching the cavity length of the laser cavity between different cavity lengths, wherein the different cavity lengths are selected such that at each of the cavity lengths the solid state laser lases at only one of the different emission wavelengths which is different from the emission wavelengths at the other of the selected cavity lengths. With the method and corresponding device an easy switching between emission wavelengths of a solid state laser is possible.

INTRACAVITY FREQUENCY-CONVERTED SOLID-STATE LASER FOR THE VISIBLE WAVELENGTH REGION

The present invention provides an intracavity frequency-converted solid state laser for the visible wavelength region. The laser comprises a semiconductor laser (1) with an extended laser cavity (2). A second laser cavity (4) is formed inside of said extended laser cavity (2). The second laser cavity (4) comprises a gain medium (3) absorbing radiation of the semiconductor laser (1) and emitting radiation at a higher wavelength in the visible wavelength region. The frequency converting gain medium (3) is formed of a rare-earth doped solid state host material. The proposed laser can be manufactured in a highly integrated manner for generating radiation in the visible wavelength region, for example in the green, red or blue wavelength region.

VERTICAL CAVITY SURFACE EMITTING LASER (VCSEL), LASER SENSOR AND METHOD OF PRODUCING A VCSEL

A vertical cavity surface emitting laser includes an optical resonator, a photodiode, and an electrical contact arrangement. The optical resonator includes a semiconductor multilayer stack. The semiconductor multilayer stack includes, in a direction of growth of the multilayer stack, a first distributed Bragg reflector, a second distributed Bragg reflector, and an active region for laser emission arranged between the first distributed Bragg reflector and second distributed Bragg reflector. The electrical contact arrangement is arranged to electrically pump the optical resonator and to electrically contact the photodiode. A reflectivity of the second distributed Bragg reflectoris higher than a reflectivity of the first distributed Bragg reflector. The photodiode has an absorbing region arranged in the second distributed Bragg reflector. A tunnel junction is arranged between the photodiode and the active region.

Heating system and method of heating a body of a preform

The invention describes a heating system (13) for heating a body (1) of a preform having a material thickness bounded by a first surface (2) and a second surface (4). The heating system (13) comprises at least a light source arrangement (12) which is arranged to emit a number of directed light beams (17) and a coupling arrangement (15, 21) realized to deliberately couple light from the light source arrangement (12) in a specific direction into the body (1) during at least a certain minimum period such that the light is essentially guided along a longer path (19) between the first (2) and second surface (4). Furthermore, the invention concerns a method of heating a body (1) of a preform.

VERTICAL CAVITY SURFACE EMITTING LASER DEVICE WITH INTEGRATED TUNNEL JUNCTION

VCSELs have a substrate, first and second electrical contacts (ECs), and an optical resonator (OR), having first and second distributed Bragg reflectors (DBRs) and an active layer between the DBRs. The first DBR is between the substrate and the active layer. One of the DBRs has: first and second parts, having different conductivity types, and each with a pair of layers with different refractive indices. A tunnel junction (TJ) is between the parts. The ECs are for electrically pumping the OR such that the TJ is reversely biased during operation of the VCSEL. Either the first DBR includes the parts, having a relative thickness of the second part to a total thickness of the first and second parts between 0.1-0.8, or the second DBR has the parts, the second part being on the TJ facing away from the active layer, and the relative thickness being between 0.15-0.6. 1. A Vertical Cavity Surface Emitting Laser device comprising:a substrate;a first electrical contact;a second electrical contact; and a first distributed Bragg reflector;', 'a second distributed Bragg reflector; and', 'an active layer for light emission,, 'an optical resonator, wherein the optical resonator compriseswherein the active layer is between the first distributed Bragg reflector and the second distributed Bragg reflector,wherein the first distributed Bragg reflector is between the substrate and the active layer, a first part with at least one pair of layers with different refractive indices; and', 'a second part with at least one pair of layers with different refractive indices,, 'wherein either the first distributed Bragg reflector or the second distributed Bragg reflector compriseswherein the first part and the second part are characterized by different conductivity types,wherein a tunnel junction is between the first part and the second part,wherein the first electrical contact and the second electrical contact are configured to electrically pump the optical resonator such that the tunnel junction ...

Vertical cavity surface emitting laser (VCSEL) with improved gain-switching behavior

A Vertical Cavity Surface Emitting Laser (VCSEL) has a mesa having an active region, which has m active layer structures (with m≥2). The active layer structures are electrically connected to each other by a tunnel junction therebetween. The mesa has an optical resonator, which has first and second DBRs. The active region is between the first and second DBRs. The VCSEL has first and second electrical contacts, which provide electrical current to the active region, and an electrical control contact, which controls gain-switched laser emission of the VCSEL by at least 1 up to m−1 active layer structures by a current between the electrical control contact and the first or second electrical contact. A current aperture is between the active region and the first or second electrode. A distance between the current aperture and a furthest active layer structure is at least three times the laser light's wavelength.

VERTICAL CAVITY SURFACE EMITTING LASER AND METHOD OF PRODUCING SAME

A Vertical Cavity Surface Emitting Laser (VCSEL) includes a layer stack of semiconductor layers having a first layer sub-stack forming a mesa, and a second layer sub-stack adjacent to the mesa in a stacking direction. Layers of the second layer sub-stack extend beyond layers of the first sub-stack in a direction perpendicular to the stacking direction. The semiconductor layers of the layer stack form an optical resonator having a first mirror, a second mirror, an active region between the first and second mirrors for laser light generation, and an oxide aperture layer forming a current aperture. The oxide aperture layer is made from Al1-xGaxAs with 0≤x≤0.05. The oxide aperture layer is a last layer of the mesa and immediately adjacent to a first layer of the second layer sub-stack. A first layer of the second layer sub-stack is a contact layer.

Laser

The invention relates to a laser (1) for emitting laser light in the visible spectral range. A rare earth doped anisotropic crystal (2) comprising a 5d-4f transition is arranged within a laser resonator (7, 8), and a pumping light source (3) pumps the crystal (2) for generating laser light in the visible spectral range by using the 5d-4f transition. The 5d-4f transition of the rare earth doped anisotropic crystal comprises an absorption band extending over several nm. Thus, pump light having a wavelength within a relatively broad wavelength range can be used. This reduces the requirements with respect to the wavelength accuracy of the pumping light source and, thus, more pumping light sources of an amount of produced pumping light sources can be used for assembling the laser, thereby reducing the amount of rejects.

OPTICALLY PUMPED SOLID-STATE LASER WITH CO-DOPED GAIN MEDIUM

The present invention relates to a solid-state laser comprising a gain medium (6) of a solid-state host material which is co-doped with Ce3+-ions and ions of a further rare-earth material. The host material is selected such that a lower edge of the 5d band of the Ce3+-ions is energetically higher than an upper lasing state of the ions of the further rare-earth material. This laser can be optically pumped by GaN laser diodes (4) in the wavelength region between 400 and 450 nm and emits laser radiation in the visible wavelength range. With this laser, in particular, a GaN diode laser pumped solid-state laser emitting in the green wavelength region can be realized.

Switchable dual wavelength solid state laser

The present invention relates to a switchable dual wavelength solid state laser with a solid state gain medium (1) which is selected to emit optical radiation at a first wavelength with a first polarization and of at least a second wavelength with a second polarization different from said first polarization when optically or electrically pumped. A polarizing device (7) is arranged within the laser cavity, said polarizing device (7) being adjustable at least between said first and said second polarization. The two end mirrors (2, 3) of the laser cavity are designed to allow lasing of the solid state laser at the first wavelength when the polarizing device (7) is adjusted to the first polarization, and to allow lasing of the solid state laser at the second wavelength when the polarizing device (7) is adjusted to the second polarization. The proposed solid state laser allows an easy switching between two emission wavelengths.

Solid state laser device with reduced temperature dependence

The present invention relates to a solid state laser device with a solid state gain medium between two resonator end mirrors (3, 5) and a GaN-based pump laser (1) arranged to optically pump the solid state gain medium. The solid state gain medium is a Pr3+-doped crystalline or polycrystalline host material (4) which has a cubic crystalline structure and highest phonon energies of 600 cm1 and provides a band gap of 5.5 eV. The proposed solid state laser can be designed to emit at several visible wavelengths with the emitted power showing a reduced dependence on the temperature of the GaN-based pump laser (1).

Light emitting semiconductor devices with getter layer

The invention describes a light emitting semiconductor device (100) comprising a substrate (120), a light emitting layer structure (155) and an AlGaAs getter layer (190) for reducing an impurity in the light emitting layer structure (155), the light emitting layer structure (155) comprising an active layer (140) and layers of varying Aluminum content, wherein the growth conditions of the layers of the light emitting layer structure (155) comprising Aluminum are different in comparison to the growth conditions of the AlGaAs getter layer (190). The AlGaAs getter layer (190) enables a reduction of the concentration of impurities like Sulfur etc. in the gas phase of a deposition equipment or growth reactor. The reduction of such impurities reduces the probability of incorporation of the impurities in the light emitting layer structure (155) which may affect the lifetime of the light emitting semiconductor device (100). The growth conditions are chosen out of the group Arsenic partial pressure ...

VERTICAL CAVITY SURFACE EMITTING LASER WITH INTEGRATED PHOTODIODE

A vertical cavity surface emitting laser (VCSEL) emits laser light. The VCSEL has an optical resonator and a photodiode. The optical resonator has: a first mirror, an active region configured to generate laser light, and a second mirror. The active region is arranged between the first mirror and the second mirror. The photodiode is integrated in the optical resonator. The photodiode has: an absorption region having a plurality of absorbing layers configured to absorb the generated laser light. The absorbing layers are arranged spaced apart from one another by a distance d which satisfies the condition: d=(2k−1)λ/(4 m). Where λ is the wavelength of the laser light in the absorption region, and k and m are natural numbers≥1.

Inhibiting unauthorized access to a laser source

The invention relates to the field of laser sources (3), and for specifically to inhibiting damage due to misuse of a laser source (3), in particular of a high-power laser source (3) provided in a consumer product (1). The proposed device (1) includes at least a laser source (3) and a safety unit (2), wherein by means of the arrangement of the safety unit (2) it is provided that potential harm caused by misuse of the laser source (3) based on an unauthorized access to the laser source (3) is confined or even prevented by reducing the power level of the output of the laser source (3) or by even completely stopping any laser output therefrom. A corresponding method of providing a laser source (3) and a further method of preventing misuse of a laser source (3) are also proposed.

High luminance solid state light source

A solid-state light source includes laser diodes that emit a laser beam with a first wavelength, a rotatable support that is arranged in a beam path of the laser beam and a reflector that is arranged between the laser diodes and the rotatable support. The rotatable support is formed of a ring or of an optically transparent disc. Further, the rotatable support is mounted to be rotatable around a rotation axis such that the laser beam impinges on a ring-shaped area of the rotatable support during rotation. Segments of the ring-shaped area include wavelength converting material that emits radiation of a second wavelength upon impingement of the laser beam. The rotatable support is mounted in a bearing that is arranged distant from the rotation axis to allow unhindered passage of the radiation directed by the reflector to the emission direction.

Method of manufacturing a part of a color ring and a part of a color ring

A method 200 of manufacturing a (part of) color ring is provided. The color ring converts a color of light emitted by a light emitter into at least one other color. The method ( 200 ) comprising the steps of: i) pressing ( 102 ) a first ring body of a first granulated precursor comprising a first luminescent material for converting the color of the light of the light emitter into a first one of the at least one other color, and ii) sintering ( 104 ) the first ring body for obtaining a first ceramic ring. The color ring comprises at least a segment of the first ceramic ring. Further, the method may comprises the steps of: iii) pressing ( 208 ) a second ring body of a second granulated precursor, wherein the first luminescent material is absent, iv) sintering ( 210 ) the second ring body for obtaining a second ceramic ring, v) segmenting ( 206 ) the first ceramic rings in at least two parts and segmenting ( 212 ) the second ceramic ring in at least two parts, and vi) forming ( 214 ) at least a part of the color ring by coupling a part of the first ceramic ring and a part of the second ceramic ring.

CERAMIC NON-CUBIC FLUORIDE MATERIAL FOR LASERS

The invention relates to a ceramic non-cubic fluoride laser material and methods of its manufacture.

OPTICAL SENSOR

An optical sensor (600) for detecting the movement of an object relative to the position of the optical sensor (600), using self-mixing interference, is described. The optical sensor (600) comprises a laser (100), a detector (200) and a filter device (500). The filter device (500) suppresses measurement signals generated by means of the detector (200) when movements of the object at a velocity below a defined threshold value cause the measurement signals. The optical sensor (600) may be used in a switch in order to enable selective switching depending on the velocity of the movement of the object.

WAVEGUIDE LASER

It is an object of the invention to provide a simple setup of a waveguide laser which allows to control the emission of specific laser wavelengths in a laser material having laser transitions of similar wavelengths. For this purpose a core ( 4 ) forming a gain medium is provided with a cladding ( 6 ) which introduces losses to an undesired laser transition but is transparent to the light of a desired laser transition. A second cladding ( 8 ) is provided for guiding the laser radiation. Pr: ZBLAN with a Tb: doped cladding may be used. Instead of the absorbing cladding ( 6 ) a photonic crystal ( 20 ) may be used. The laser is end-pumped by a laser diode ( 14 ).

APPARATUS FOR DETERMINING A FLOW PROPERTY OF A FLUID

The invention relates to an apparatus (1) for determining a flow property of a fluid (2). The apparatus comprises a distance and velocity determination unit (3) for determining distances of elements of the fluid to the distance and velocity determination unit (3) and for determining velocities of the elements at the same time based on a self-mixing interference signal. The apparatus (1) comprises further a flow determination unit (4) for determining the flow property of the fluid (2) based on at least one of the determined distances and velocities. This allows determining the flow property, even if the fluid (2) is optically thick.

LIGHTING APPARATUS FOR GENERATING LIGHT

The invention relates to a lighting apparatus for generating light. A primary light generator generates primary light (), which is converted by a light converting material () into secondary light (), wherein the primary light is directed to a primary surface () of the light converting material. An enclosure () comprising a transparent cover () hermetically encloses the light converting material, wherein the transparent cover is transparent to the primary light and located on the primary surface of the light converting material. The enclosure increases the photostability of the light converting material. This allows increasing the intensity of the primary light by, for example, increasing the power of the primary light and, thus,of the secondary light, and/or by focusing the primary light onto a smaller area on the primary surface, thereby allowing decreasing the optical Étendue of the secondary light, without damaging the light converting material. 1. A lighting apparatus for generating light , the lighting apparatus comprising:a primary light generator for generating primary light,a light converting material for converting the primary light into secondary light wherein the primary light generator and the light converting material are arranged for allowing the primary light to be directed to a primary surface-;; the light converting material,an enclosure for hermetically enclosing the light converting material, wherein the enclosure comprises a transparent cover, which is transparent to the primary light and which is located on the primary surface is of the light converting material.2. The lighting apparatus as defined in claim 1 , wherein the transparent cover comprises a planar outer surface which is located on the primary surface of the light converting material.3. The lighting apparatus as defined in claim 1 , wherein the transparent cover comprises a curved outer surface claim 1 , which is directed away from the light converting material claim 1 , for ...

LIGHT-EMITTING DEVICE WITH A LUMINESCENT MEDIUM, CORRESPONDING LIGHTING SYSTEM COMPRISING THE LIGHT-EMITTING DEVICE AND CORRESPONDING LUMINESCENT MEDIUM

The invention relates to a light emitting device ( 1 ) with high colour rendering comprising a wavelength converting member ( 2 ) with a luminescent medium for wavelength conversion of blue light and/or ultraviolet light ( 10 ) into red light and/or yellow and/or green light and a light source ( 3 ) emitting blue light ( 10 ) and/or ultraviolet light arranged to pump the luminescent medium, said luminescent medium essentially having a main phase of a solid state host material which is doped with Ce 3+ -ions. According to the invention the host material comprises ions of a further rare-earth material Ln, wherein the host material is selected such that the emission energy of the 5d-4f emission on Ce 3+ -ions is energetically higher than the absorption energy into an upper 4f n state of the further rare-earth material Ln, and wherein the light emission of wavelength converted light is caused by an intra-atomic 4f n -4f n transition within the ions of the further rare-earth material. The invention further relates to a corresponding lighting system comprising the light-emitting device and a corresponding luminescent medium.

DIODE PUMPED SOLID-STATE LASER WITH IMPROVED PUMP LIGHT ABSORPTION

For a diode pumped solid-state laser, measures to improve the pump light absorption in anisotropic crystals are proposed. The proposed measures reduce the dependency of the pump light absorption on the diode current and the diode temperature as well as on the detuning of the pump diode from the absorption line. These measures include sending the pump radiation twice through the crystal, placement of the laser crystal in an orientation that does not exhibit the optimum absorption and the use of a retarder. 1. A diode pumped solid state laser device , comprisinga pump laser diode and an output coupler which reflects back the fraction of said pump laser light longitudinally transmitted through said laser crystal,', 'an anisotropic laser crystal having two different absorption coefficients for pump light polarized along a first direction transversally to the longitudinal direction of the solid state laser and a second direction vertically to said first direction, wherein said anisotropic laser crystal and said pump laser diode are mutually oriented so that the polarization of said pump laser light has a component both along said first and said second direction, and', 'a retarder, said retarder converting said pump light from linearly polarized light into elliptically or circularly polarized light., 'a laser crystal forming at least a part of a solid state laser which emits laser light at a wavelength different from the wavelength of the laser light emitted from said pump laser diode, and said solid state laser being pumped by said pump laser diode, wherein said pump laser diode is arranged to inject its pump laser light in longitudinal direction into said laser crystal, said diode pumped solid state laser device comprising at least one of'}2. The diode pumped solid state laser device as claimed in claim 1 , wherein said solid state laser comprises a wavelength selective mirror terminating the laser cavity of said solid state laser at the opposite end of said output ...

LASER

The invention relates to a laser () for emitting laser light in the visible spectral range. A rare earth doped anisotropic crystal () comprising a -transition is arranged within a laser resonator (), and a pumping light source () pumps the crystal () for generating laser light in the visible spectral range by using the -transition. The -transition of the rare earth doped anisotropic crystal comprises an absorption band extending over several nm. Thus, pump light having a wavelength within a relatively broad wavelength range can be used. This reduces the requirements with respect to the wavelength accuracy of the pumping light source and, thus, more pumping light sources of an amount of produced pumping light sources can be used for assembling the laser, thereby reducing the amount of rejects. 1. A laser for emitting laser light in the visible spectral range , the laser comprising:a laser resonator, characterized by{'b': 5', '4, 'i': d', 'f, 'a rare earth doped anisotropic crystal comprising a -transition, wherein the crystal is arranged within the laser resonator,'}{'b': 5', '4, 'i': d', 'f, 'a pumping light source for pumping the crystal by illuminating the crystal with pump light for generating laser light in the visible spectral range by using the -transition.'}2. The laser as defined in claim 1 , wherein the crystal and the pumping light source are adapted such that the generated laser light is within a green wavelength range.354df. The laser as defined in claim 1 , wherein the crystal is adapted to comprise a specific indicatrix axis claim 1 , wherein the sum of the cross section of the stimulated emission at a visible wavelength range on the -transition of a rare earth doping element with respect to the specific indicatrix axis and the cross section of the excited state absorption at the same visible wavelength range with respect to the same specific indicatrix axis is positive claim 1 , wherein the cross section of the stimulated emission is denoted with a ...

METHOD OF MANUFACTURING A PART OF A COLOR RING AND A PART OF A COLOR RING

A method 200 of manufacturing a (part of) color ring is provided. The color ring converts a color of light emitted by a light emitter into at least one other color. The method ( 200 ) comprising the steps of: i) pressing ( 102 ) a first ring body of a first granulated precursor comprising a first luminescent material for converting the color of the light of the light emitter into a first one of the at least one other color, and ii) sintering ( 104 ) the first ring body for obtaining a first ceramic ring. The color ring comprises at least a segment of the first ceramic ring. Further, the method may comprises the steps of: iii) pressing ( 208 ) a second ring body of a second granulated precursor, wherein the first luminescent material is absent, iv) sintering ( 210 ) the second ring body for obtaining a second ceramic ring, v) segmenting ( 206 ) the first ceramic rings in at least two parts and segmenting ( 212 ) the second ceramic ring in at least two parts, and vi) forming ( 214 ) at least a part of the color ring by coupling a part of the first ceramic ring and a part of the second ceramic ring.

SWITCHABLE DUAL WAVELENGTH SOLID STATE LASER

The present invention relates to a switchable dual wavelength solid state laser with a solid state gain medium () which is selected to emit optical radiation at a first wavelength with a first polarization and of at least a second wavelength with a second polarization different from said first polarization when optically or electrically pumped. A polarizing device () is arranged within the laser cavity, said polarizing device () being adjustable at least between said first and said second polarization. The two end mirrors () of the laser cavity are designed to allow lasing of the solid state laser at the first wavelength when the polarizing device () is adjusted to the first polarization, and to allow lasing of the solid state laser at the second wavelength when the polarizing device () is adjusted to the second polarization. The proposed solid state laser allows an easy switching between two emission wavelengths. 1. Solid state laser device with switchable wavelength , the device having a laser cavity and comprisingtwo resonator end mirrors disposed within the laser cavity;a solid state gain medium disposed between the resonator end mirrors, said solid state gain medium being selected to emit optical radiation at a first wavelength with a first polarization and of at least a second wavelength with a second polarization different from said first polarization, when optically or electrically pumped, anda polarizing device disposed within the laser cavity, said polarizing device being adjustable at least between said first and said second polarization, wherein the two resonator end mirrors facilitate lasing of the solid state laser at said first wavelength when the polarizing device is adjusted to the first polarization, and at said second wavelength when the polarizing device is adjusted to the second polarization.2. Solid state laser device according to claim 1 , wherein said solid state gain medium is formed of a doped crystal of at least biaxial symmetry.3. Solid ...

VERTICAL CAVITY SURFACE EMITTING LASER DEVICE WITH MONOLITHICALLY INTEGRATED PHOTODIODE

A vertical cavity surface emitting laser device includes: an optical resonator; a photodiode; and a contact arrangement. The optical resonator includes: two distributed Bragg reflectors (DBRs) and an active region between the DBRs. The photodiode has a light absorption region in the optical resonator. The contact arrangement provides drive current to pump the optical resonator, and contacts the photodiode. The active region has an InGaAs layer, where 0≤x<1. The light absorption region has an InGaAs layer, where 0x. The InGaAs layer is an intrinsic layer of the light absorption region. The InGaAs layer is 15-50 nm thick. The light absorption region has an undoped layer with a material different from the InGaAs layer. The InGaAs layer is immediately adjacent to the undoped layer. An intrinsic zone of the light absorption region is at least 70 nm thick. 1. A vertical cavity surface emitting laser (VCSEL) device , the VCSEL device comprising:an optical resonator;a photodiode; andan electrical contact arrangement, a first distributed Bragg reflector;', 'a second distributed Bragg reflector; and', 'an active region for light emission,, 'wherein the optical resonator compriseswherein the active region is arranged between the first distributed Bragg reflector and the second distributed Bragg reflector,wherein the photodiode comprises a light absorption region arranged in the optical resonator,wherein the electrical contact arrangement is arranged to provide an electrical drive current to electrically pump the optical resonator, and to electrically contact the photodiode,{'sub': x', '1-x, 'wherein the active region comprises at least one InGaAs layer,'}wherein 0≤x<1,{'sub': y', '1-y, 'wherein the light absorption region comprises at least one InGaAs layer,'}wherein 0 Подробнее

OPTICALLY PUMPED SOLID-STATE LASER AND LIGHTING SYSTEM COMPRISING SAID SOLID-STATE LASER

The invention relates to a solid-state laser device () comprising a gain medium () essentially having a main phase of a solid state host material () which is doped with rare-earth ions. According to the invention at least a portion of the rare-earth ions are Ce-ions () with at least one 4f-state () and at least one 5d-band () energetically between the highest valence state and the lowest conduction state of the host material (), wherein 1. Solid-state laser device comprising a gain medium essentially having a main phase of a solid state host material which is doped with rare-earth ions , wherein at least a portion of the rare-earth ions are Ce-ions with at least one 4f-state and at least one 5d-band energetically between the highest valence state and the lowest conduction state of the host material , whereinthe highest 4f-state and the bottom edge of the 5d-band have a first energy-level distance andthe lowest 4f-state and the upper edge of the 5d-band have a second energy-level distance,wherein the host material is selected such that the resulting gain medium has an energy range devoid of unoccupied states for disabling excited state absorption, the energy range is located betweena lower energy which is by the value of the first energy level distance above the bottom edge of the 5d-band anda higher energy which is by the value of the second energy level distance above the upper edge of the 5d-band.2. Solid-state laser device according to claim 1 , wherein the 5d band is thermally isolated from the conduction band at least by 0.5 eV.3. Solid-state laser device according to claim 1 , wherein the rare-earth ions are{'sup': '3+', 'Ce-ions or'}{'sup': 3+', '3+', '3+', '3+', '3+', '3+', '3+, 'mixtures of Ce-ions and other rare earth-ions, the other rare earth-ions selected from the group of Pr-, Sm-, Eu-, Tb-, Dy-, and Tm-ions.'}4. Solid-state laser device according to claim 1 , wherein the host material comprises (YGdLu)AlGaO— claim 1 , wherein 1≦z≦5; 0≦x≦1; 0≦y'1 and x ...

INTRACAVITY UPCONVERSION LASER

The present invention relates to an upconversion laser system comprising at least a semiconductor laser having a gain structure ( 4 ) arranged between a first mirror ( 5 ) and a second mirror ( 6 ), said first ( 5 ) and said second mirror ( 6 ) forming a laser cavity ( 7 ) of the semiconductor laser, and an upconversion laser for upconverting a fundamental radiation of said semiconductor laser. The upconversion laser system of the present invention is characterized in that the upconversion laser is arranged in the laser cavity ( 7 ) of the semiconductor laser. The proposed upconversion laser system has a compact design.

METHOD FOR INCREASING THE CONTENT OF CE3+ IN LASER MATERIALS

The invention relates to a method of making Cecontaining laser materials with a fast cooling rate. This has been shown to dramatically increase the absorption rate of the 4f-5d-transition of Cewithin the laser material 1. A method of manufacturing Cerium-containing laser materials with an emittance in the visible wavelength area , comprising the steps of:a) Heating the laser material and/or suitable precursors to a temperature of ≧1800° C.{'sub': 1−x', '2', '4', 'x', '1−x', '2', '4', 'x, 'b) Cooling to a temperature of ≦300° C. within ≦40 h (cooling time), wherein the laser material is Ca(Sc,Mg)O:Ceor CaScO:Ce'}2. The method of claim 1 , whereby the cooling time is preferably ≦12 h claim 1 , more preferably ≦9 h.3. The method of claim 1 , whereby in step a) the laser material and/or suitable precursors is heated to a temperature of ≧2000° C.4. The method of claim 1 , wherein the cooling time is ≦−64/ln([Ce])h claim 1 , preferably ≦50/ln([Ce])h claim 1 , more preferably ≦−40/ln([Ce])h claim 1 , wherein [Ce] is the molar dotation level of Ce.5. The method of claim 1 , wherein the laser material is an orthorhombic material showing an 5d-4f transition.6. (canceled)7. The method of claim 1 , wherein the dotation in the laser material is ≧0.001.8. The method of claim 1 , wherein the dotation in the laser material is ≧0.0025 and ≦0.2 claim 1 , preferably ≧0.004 and ≦0.1.9. A system comprising a laser material made according to claim 1 , the system being used in one or more of the following applications:Solid-state lasersdigital projectionfibre-optical applicationsmedical applications of solid-state lasersheating applicationsscintillation applicationsx-ray detectors-ray detectorshigh-energy particle detectorsgeneration of ultrashort pulsesFluorescence microscopySpectroscopyBiophotonicsPhotolithography The present invention is directed to laser materials comprising Ceand methods of their preparation.Solid-state light sources are currently entering many different lighting ...

INHIBITING UNAUTHORIZED ACCESS TO A LASER SOURCE

The invention relates to the field of laser sources (), and for specifically to inhibiting damage due to misuse of a laser source (), in particular of a high-power laser source () provided in a consumer product (). The proposed device () includes at least a laser source () and a safety unit (), wherein by means of the arrangement of the safety unit () it is provided that potential harm caused by misuse of the laser source () based on an unauthorized access to the laser source () is confined or even prevented by reducing the power level of the output of the laser source () or by even completely stopping any laser output therefrom. A corresponding method of providing a laser source () and a further method of preventing misuse of a laser source () are also proposed. 1. A device comprisinga laser source anda safety unit,{'b': '30', 'wherein the safety unit comprises a detector for detecting () unauthorized access to the laser source, and the safety unit is adapted for causing, upon unauthorized access to the laser source,'}a rendering of the laser source inoperable, ora reduction of the outputtable power of the laser source such that the laser source is permanently disabled.2. The device according to claim 1 , further comprising{'b': '5', 'an interface () to the outside of the device,'}wherein the interface is adapted for providing an authorizing action for preventing the safety unit from causing the rendering and/or the reduction, thus allowing for authorized access to the laser source.3. The device according to claim 2 ,wherein the interface comprises a user interface adapted for accepting a user input, wherein the interface is adapted for providing the authorizing action in case the user input corresponds to a predetermined access code.4. The device according to claim 2 ,wherein the interface is adapted for being coupled to an external authorizing device, wherein the interface is adapted for providing the authorizing action in case the external authorizing device ...

Laser device with adjustable polarization

The invention describes a laser device (10) comprising an array (50) of laser emitters (100) and a control unit (200), the array (50) comprises at least a first sub array (110) of laser emitters and a second sub array (120) of laser emitters, wherein the first sub array (110) emits laser light of a first polarization and the second sub array (120) emits laser light of a second polarization being different from the first polarization, and wherein the control unit (200) is adapted to control the first sub array (110) and the second sub array (120) such that the polarization of the laser light emitted by the array (50) can be changed. The invention further describes a sensor device (300) and an optical detection system (400) comprising such a laser device (10). Furthermore, a method of determining the shape of an object by means of the optical detection system (400) is described.

VERTICAL CAVITY SURFACE EMITTING LASER (VCSEL) WITH IMPROVED GAIN-SWITCHING BEHAVIOR

A Vertical Cavity Surface Emitting Laser (VCSEL) has a mesa having an active region, which has m active layer structures (with m≥2). The active layer structures are electrically connected to each other by a tunnel junction therebetween. The mesa has an optical resonator, which has first and second DBRs. The active region is between the first and second DBRs. The VCSEL has first and second electrical contacts, which provide electrical current to the active region, and an electrical control contact, which controls gain-switched laser emission of the VCSEL by at least 1 up to m-1 active layer structures by a current between the electrical control contact and the first or second electrical contact. A current aperture is between the active region and the first or second electrode. A distance between the current aperture and a furthest active layer structure is at least three times the laser light's wavelength. 1. A Vertical Cavity Surface Emitting Laser comprising at least one mesa ,wherein the at least one mesa comprises an active region,wherein the active region comprises a number of m active layer structures with m≥2,wherein the active layer structures are electrically connected to each other by a tunnel junction arranged between the active layer structures,wherein the at least one mesa further comprises an optical resonator,wherein the optical resonator comprises a first Distributed Bragg Reflector and a second Distributed Bragg Reflector,wherein the active region is arranged between the first Distributed Bragg Reflector and the second Distributed Bragg Reflector,wherein the Vertical Cavity Surface Emitting Laser further comprises a first electrical contact and a second electrical contact,wherein the first electrical contract and the second electrical contact are arranged to provide an electrical current to the active region,wherein the Vertical Cavity Surface Emitting Laser further comprises an electrical control contact,wherein the electrical control contact is ...

All-Solid State Uv Laser System

The present invention relates to an all-solid state UV laser system comprising at least one semiconductor laser (10) in a VECSEL configuration. The gain structure (3) in this semiconductor laser (10) emits fundamental radiation in a wavelength range which can be frequency doubled to wavelengths in the UV region. The frequency doubling is achieved with a nonlinear optical crystal (6) for second harmonic generation arranged inside the extended cavity of the semiconductor laser (10). By electrically pumping of the semiconductor laser wavelengths below 200 nm can be efficiently generated with already known semiconductor materials like GaN. The proposed UV laser system is compact and can be fabricated and operated at low costs compared to UV excimer lasers.

SYSTEM FOR AND METHOD OF HEATING OBJECTS IN A PRODUCTION LINE

A system and method ( 10 ) for heating objects (O) during a thermal treatment process in a production line (P) is described. The system ( 10 ) comprises a transport system ( 11 ), a minor arrangement ( 201, 202, 203, 204, 205, 206 ) comprising a first mirror surface ( 21, 21′, 21″ ) and a second minor surface ( 22, 22′, 22″ ) arranged at opposite sides, so that the objects (O) may be transported between the minor surfaces ( 21, 22, 21′, 22′, 21″, 22″ ) along the production line and a radiation device ( 30 ) comprising a number of lasers for generating light (L). The radiation device ( 30 ) and the mirror arrangement ( 201, 202, 203, 204, 205, 206 ) are constructed such that the main direction (R) of light (L) that enters the mirror arrangement ( 201, 202, 203, 204, 205, 206 ) is directed towards the first mirror surface ( 21, 21′, 21″ ) at an angle to the production line (P), and the light (L) subsequently undergoes multiple reflections between the mirror surfaces ( 21, 22, 21′, 22′, 21″, 22″ ) so that a series of multiple reflections of the light (L) travels in the transport direction (OT) along at least a section of the minor surface ( 21, 22, 21′, 22′, 21″, 22″ ) or travels against the transport direction (OT) along at least a section of the minor surface ( 21, 22, 21′, 22′, 21″, 22″ ) and heats the objects (O) being transported between the minor surfaces ( 21, 22, 21′, 22′, 21″, 22″ ).

VCSEL WITH INCREASED WAVELENGTH DEPENDENCE ON DRIVING CURRENT

A Vertical Cavity Surface Emitting Laser VCSEL, includes an optical resonator with a first reflector, a second reflector, and an active region for laser emission arranged between the first reflector and the second reflector and remaining regions outside of the active region, and an electrical contact arrangement configured to provide an electrical drive current to electrically pump the optical resonator. The optical resonator further comprises a loss layer introducing optical and/or electrical losses to increase wavelength shift of the laser emission when varying the drive current. If the loss layer is an optical loss layer, the optical losses introduced by the loss layer are higher than the sum of the optical losses in the remaining regions. If the loss layer is an electrical loss layer, the electrical losses introduced by the loss layer are higher by a factor of at least 5 than the electrical losses in the remaining regions.

Method of determining operation conditions of a laser-based particle detector

A method for determining operating conditions of a particle detector that includes a multimode Vertical Cavity Surface Emitting Laser (VCSEL) includes providing an electrical drive current to the multimode VCSEL such that a laser beam is emitted by the multimode VCSEL and varying the electrical drive current within a predefined range of electrical drive currents. The method further includes determining, as a function of the electrical drive current, an intensity signal of an optical wave within a laser cavity of the multimode VCSEL, determining, as a function of the electrical drive current, a noise measure of the intensity signal, determining a range of electrical drive currents for which the noise measure is below a predefined threshold noise measure value, and determining operating conditions of the particle detector by choosing an electrical drive current for particle detection out of the determined low noise range of electrical drive currents.

SOLID STATE LASER DEVICE WITH REDUCED TEMPERATURE DEPENDENCE

The present invention relates to a solid state laser device with a solid state gain medium between two resonator end mirrors (3, 5) and a GaN-based pump laser (1) arranged to optically pump the solid state gain medium. The solid state gain medium is a Pr3+-doped crystalline or polycrystalline host material (4) which has a cubic crystalline structure and highest phonon energies of 600 cm and provides a band gap of 5.5 eV. The proposed solid state laser can be designed to emit at several visible wavelengths with the emitted power showing a reduced dependence on the temperature of the GaN-based pump laser (1).

Laser projection system based on a luminescent screen

A laser projection system includes at least one laser light source, a projection screen and a spatial light modulator for projecting a laser beam of the laser light source to form an image on the projection screen. The projection screen includes a luminescent layer which upon excitation by the laser beam emits blue light. The luminescent layer contains MSi6aAlaN8aOx+a:Eu2+ (with M=Sr, Ba,; 0x1; 0a1) as a luminescent material. With this material laser light of a laser diode emitting in the wavelength region of 405 nm can be converted to blue light of 450 nm with high efficiency. The proposed projection system, therefore, is suitable for RGB projection using laser diodes as laser light sources.

VECSEL-PUMPED SOLID-STATE LASER

The present invention relates to a solid-state laser system constituted bya solid-state laser whichis optically pumped by a vertical extended cavity surface emitting laser (VECSEL). The solid-state laser comprises a solid-state laser medium (11) arranged in a laser cavity which consists oftwo resonator cavitymirrors (10, 12), a first of saidcavity mirrors (12) being designed as an outcoupling mirror of saidsolid-state 5 laser and a second of saidcavity mirrors (10) being formed to allow optical pumping of saidsolid-state laser medium (11) through saidsecond cavity mirror (10). In the proposed solid-state laser system, the extended cavity mirror (7) of the VECSEL is constituted byone of the resonator cavity mirrors (10, 12) of the solid-state-laser. The proposed laser system provides an improved conversion efficiency and a highly 10 integrated design.

Method and Circuit Arrangement For the Operation of a Discharge Lamp

A method and a circuit arrangement for the operation of a discharge lamp, in particular of a high-pressure gas mercury discharge lamp (HID[high intensity discharge]) lamp or a UHP [ultra high performance] lamp, are described, which are used to improve the color rendering index of the light. This is essentially achieved by feeding the lamp current on which current pulses with a suitably adjusted amplitude Ip and/or duration ?p and/or repetition rate f are superimposed.

System for and method of heating objects in a production line

A system and method ( 10 ) for heating objects (O) during a thermal treatment process in a production line (P) is described. The system ( 10 ) comprises a transport system ( 11 ), a minor arrangement ( 201, 202, 203, 204, 205, 206 ) comprising a first mirror surface ( 21, 21′, 21″ ) and a second minor surface ( 22, 22′, 22″ ) arranged at opposite sides, so that the objects (O) may be transported between the minor surfaces ( 21, 22, 21′, 22′, 21″, 22″ ) along the production line and a radiation device ( 30 ) comprising a number of lasers for generating light (L). The radiation device ( 30 ) and the mirror arrangement ( 201, 202, 203, 204, 205, 206 ) are constructed such that the main direction (R) of light (L) that enters the mirror arrangement ( 201, 202, 203, 204, 205, 206 ) is directed towards the first mirror surface ( 21, 21′, 21″ ) at an angle to the production line (P), and the light (L) subsequently undergoes multiple reflections between the mirror surfaces ( 21, 22, 21′, 22′, 21″, 22″ ) so that a series of multiple reflections of the light (L) travels in the transport direction (OT) along at least a section of the minor surface ( 21, 22, 21′, 22′, 21″, 22″ ) or travels against the transport direction (OT) along at least a section of the minor surface ( 21, 22, 21′, 22′, 21″, 22″ ) and heats the objects (O) being transported between the minor surfaces ( 21, 22, 21′, 22′, 21″, 22″ ).

HEATING SYSTEM AND METHOD OF HEATING A BODY OF A PREFORM

The invention describes a heating system (13) for heating a body (1) of a preform having a material thickness bounded by a first surface (2) and a second surface (4). The heating system (13) comprises at least a light source arrangement (12) which is arranged to emit a number of directed light beams (17) and a coupling arrangement (15, 21) realized to deliberately couple light from the light source arrangement (12) in a specific direction into the body (1) during at least a certain minimum period such that the light is essentially guided along a longer path (19) between the first (2) and second surface (4). Furthermore, the invention concerns a method of heating a body (1) of a preform.

LIGHT EMITTING SEMICONDUCTOR DEVICES WITH GETTER LAYER

The invention describes a light emitting semiconductor device () comprising a substrate (), a light emitting layer structure () and an AlGaAs getter layer () for reducing an impurity in the light emitting layer structure (), the light emitting layer structure () comprising an active layer () and layers of varying Aluminum content, wherein the growth conditions of the layers of the light emitting layer structure () comprising Aluminum are different in comparison to the growth conditions of the AlGaAs getter layer (). The AlGaAs getter layer () enables a reduction of the concentration of impurities like Sulfur etc. in the gas phase of a deposition equipment or growth reactor. The reduction of such impurities reduces the probability of incorporation of the impurities in the light emitting layer structure () which may affect the lifetime of the light emitting semiconductor device (). The growth conditions are chosen out of the group Arsenic partial pressure, Oxygen partial pressure, deposition temperature, total deposition pressure and deposition rate of Aluminum. The invention further relates to a corresponding method of manufacturing such a light emitting semiconductor device (). 1. A light emitting semiconductor device comprising a substrate , a light emitting layer structure and an AlGaAs getter layer for reducing an impurity in the light emitting layer structure , the light emitting layer structure comprising an active layer and layers of varying Aluminum content , wherein a first concentration of the impurity within the AlGaAs getter layer is at least 50% higher than a second concentration of the impurity in the layers of the light emitting layer structure comprising Aluminum , wherein the AlGaAs getter layer comprises a sublayer in which an Aluminum content varies with less than 0.5%/nm between a first Aluminum content and a second Aluminum content.2. The light emitting semiconductor device according to claim 1 , wherein the impurity incorporated in the AlGaAs ...

High luminance solid state light source

The present invention relates to a solid-state light source comprising one or several laser diodes ( 1 ) emitting a laser beam with a first wavelength, a rotatable support ( 6 ) arranged in a beam path of the laser beam and a reflector ( 4 ) arranged between the laser diodes ( 1 ) and the rotatable support ( 6 ). The rotatable support ( 6 ) is formed of a ring or of an optically transparent disc mounted to be rotatable around a rotation axis ( 9 ) such that the laser beam impinges on a ring-shaped area ( 7 ) of the rotatable support ( 6 ) during rotation. One or several segments of the ring-shaped area ( 7 ) comprise at least one wavelength converting material ( 8 ) emitting radiation of a second wavelength upon impingement of the laser beam. The reflector ( 4 ) allows the passage of the laser beam through a central portion of the reflector ( 4 ), collects the radiation emitted from a location of impingement of the laser beam on the ring-shaped area ( 7 ) and directs the collected radiation to an emission direction. The support ( 6 ) is mounted in a bearing ( 10 ) arranged distant from the rotation axis ( 9 ) to allow unhindered passage of the radiation directed by the reflector ( 4 ) to the emission direction. The arrangement of the reflector between the laser diodes and the rotatable support and the location of the bearing for the support distant from the rotation axis allow a compact design of the solid state light source in connection with a high luminescent efficiency.

LASER DEVICE WITH ADJUSTABLE POLARIZATION

The invention describes a laser device () comprising an array () of laser emitters () and a control unit (), the array () comprises at least a first sub array () of laser emitters and a second sub array () of laser emitters, wherein the first sub array () emits laser light of a first polarization and the second sub array () emits laser light of a second polarization being different from the first polarization, and wherein the control unit () is adapted to control the first sub array () and the second sub array () such that the polarization of the laser light emitted by the array () can be changed. The invention further describes a sensor device () and an optical detection system () comprising such a laser device (). Furthermore, a method of determining the shape of an object by means of the optical detection system () is described. 1. A laser device comprising an array of laser emitters and a control unit , the array comprising at least a first sub array of laser emitters and a second sub array of laser emitters , wherein the first sub array emits laser light of a first polarization and the second sub array emits laser light of a second polarization being different from the first polarization , wherein the first sub array and/or the second sub array comprises subsets of the laser emitters and the control unit is adapted to control the first sub array and the second sub array such that the polarization of the laser light emitted by the array can be changed , wherein the control unit is further adapted to control the subsets of the laser emitters of the first sub array and/or the second sub array independently , and wherein at least the laser light emitted by a first subset is not coherent to laser light emitted by a second subset , and wherein the control unit is adapted to control the coherence of the laser light emitted by the laser device by means of the at least first subset and the at least second subset.2. The laser device according to claim 1 , wherein the ...

METHOD OF DETERMINING OPERATION CONDITIONS OF A LASER-BASED PARTICLE DETECTOR

A method for determining operating conditions of a particle detector that includes a multimode Vertical Cavity Surface Emitting Laser (VCSEL) includes providing an electrical drive current to the multimode VCSEL such that a laser beam is emitted by the multimode VCSEL and varying the electrical drive current within a predefined range of electrical drive currents. The method further includes determining, as a function of the electrical drive current, an intensity signal of an optical wave within a laser cavity of the multimode VCSEL, determining, as a function of the electrical drive current, a noise measure of the intensity signal, determining a range of electrical drive currents for which the noise measure is below a predefined threshold noise measure value, and determining operating conditions of the particle detector by choosing an electrical drive current for particle detection out of the determined low noise range of electrical drive currents. 1. A method for determining operating conditions of a particle detector for detecting a particle density of particles with a size of less than 20 μm in a fluid , wherein the particle detector include a multimode Vertical Cavity Surface Emitting Laser (VCSEL) , the method comprising:providing an electrical drive current to the multimode VCSEL such that a laser beam is emitted by the multimode VCSEL;varying the electrical drive current within a predefined range of electrical drive currents;determining, as a function of the electrical drive current, an intensity signal of an optical wave within a laser cavity of the multimode VCSEL;determining, as a function of the electrical drive current, a noise measure of the intensity signal;determining a range of electrical drive currents for which the noise measure is below a predefined threshold noise measure value;determining at least a part of the operating conditions of the particle detector by choosing an electrical drive current for particle detection out of the determined low ...

Heating system and method of heating a body of a preform

The invention describes a heating system (13) for heating a body (1) of a preform having a material thickness bounded by a first surface(2)and a second surface (4). The heating system (13) comprises at least a light source arrangement (12) which is arranged to emit a number of directed light beams (17) and a coupling arrangement (15, 21) realized to deliberately couple light from the light source arrangement (12) in a specific direction into the body (1) during at least a certain minimum period such that the light is essentially guided along a longer path (19) between the first (2) and second surface (4).Furthermore, the invention concerns a method of heating a body (1) of a preform.

Light-emitting device with a luminescent medium, corresponding lighting system comprising the light-emitting device and corresponding luminescent medium

The invention relates to a light emitting de-vice (1) with high colour rendering comprising a wave-length converting member (2) with a luminescent medium for wavelength conversion of blue light and/or ultraviolet light (10) into red light and/or yellow and/or green light and a light source (3) emitting blue light (10) and/or ultra-violet light arranged to pump the luminescent medium, said luminescent medium essentially having a main phase of a solid state host material which is doped with Ce3+ --ions. According to the invention the host material com-prises ions of a further rare-earth material Ln, wherein the host material is selected such that the emission energy of the 5d-4f emission on Ce3+ -ions is energetically higher than the absorption energy into an upper 4fn state of the further rare-earth material Ln, and wherein the light emis-sion of wavelength converted light is caused by an intra--atomic 4fn- 4fn transition within the ions of the further rare-earth material. The invention further relates to a cor-responding lighting system comprising the light-emitting device and a corresponding luminescent medium.

Intracavity upconversion laser

The present invention relates to an upconversion laser system comprising at least a semiconductor laser having a gain structure (4) arranged between a first mirror (5) and a second mirror (6), said first (5) and said second mirror (6) forming a laser cavity (7) of the semiconductor laser, and an upconversion laser for upconverting a fundamental radiation of said semiconductor laser. The upconversion laser system of the present invention is characterized in that the upconversion laser is arranged in the laser cavity (7) of the semiconductor laser. The proposed upconversion laser system has a compact design.

Vertical Cavity Surface Emitting Laser device with integrated tunnel junction

L'invention décrit un dispositif Laser à Emission de Surface à Cavité Verticale (VCSEL) comprenant un premier (105) et un deuxième contact électrique (150) et un résonateur optique comprenant un premier (115) et un deuxième réflecteur de Bragg (125) et une couche active (120) pour une émission de lumière, agencée entre les réflecteurs de Bragg distribués. L'un ou l'autre des réflecteurs de Bragg distribués comprend une première partie (115-1, 125-1) pourvue d'une paire de couches d'indices de réfraction différents et une deuxième partie (115-2, 125-2) pourvue d'une paire de couches d'indices de réfraction différents. Les première et deuxième parties sont caractérisées par différents types de conductivité, et une jonction tunnel (130) est agencée entre elles. Les premier et deuxième contacts électriques sont agencés pour pomper électriquement le résonateur optique de sorte que la jonction tunnel soit inversement polarisée pendant le fonctionnement du dispositif VCSEL. La jonction tunnel est agencée en une position optimisée dans le premier ou le deuxième réflecteur de Bragg distribué. The invention discloses a Vertical Cavity Surface Emitting Laser (VCSEL) device comprising a first (105) and a second electrical contact (150) and an optical resonator comprising a first (115) and a second Bragg reflector (125) and an active layer (120) for light emission arranged between the distributed Bragg reflectors. One or the other of the distributed Bragg reflectors comprises a first portion (115-1, 125-1) provided with a pair of different refractive index layers and a second portion (115-2, 125-2). ) provided with a pair of different refractive index layers. The first and second parts are characterized by different types of conductivity, and a tunnel junction (130) is arranged between them. The first and second electrical contacts are arranged to electrically pump the optical resonator so that the tunnel junction is inversely polarized during ...

Inhibiting unauthorized access to a laser source

The invention relates to the field of laser sources (3), and for specifically to inhibiting damage due to misuse of a laser source (3), in particular of a high-power laser source (3) provided in a consumer product (1). The proposed device (1) includes at least a laser source (3) and a safety unit (2), wherein by means of the arrangement of the safety unit (2) it is provided that potential harm caused by misuse of the laser source (3) based on an unauthorized access to the laser source (3) is confined or even prevented by reducing the power level of the output of the laser source (3) or by even completely stopping any laser output therefrom. A corresponding method of providing a laser source (3) and a further method of preventing misuse of a laser source (3) are also proposed.

Vecsel-pumped solid-state laser

The present invention relates to a solid-state laser system constituted bya solid-state laser whichis optically pumped by a vertical extended cavity surface emitting laser (VECSEL). The solid-state laser comprises a solid-state laser medium (11) arranged in a laser cavity which consists oftwo resonator cavitymirrors (10, 12), a first of saidcavity mirrors (12) being designed as an outcoupling mirror of saidsolid-state 5 laser and a second of saidcavity mirrors (10) being formed to allow optical pumping of saidsolid-state laser medium (11) through saidsecond cavity mirror (10). In the proposed solid-state laser system, the extended cavity mirror (7) of the VECSEL is constituted byone of the resonator cavity mirrors (10, 12) of the solid-state-laser. The proposed laser system provides an improved conversion efficiency and a highly 10 integrated design.

Cerium activated phosphors co-doped with further rare earth and light-emitting device using the same

The invention relates to a light emitting device (1) with high colour rendering comprising a wavelength converting member (2) with a luminescent medium for wavelength conversion of blue light and/or ultraviolet light (10) into red light and/or yellow and/or green light and a light source (3) emitting blue light (10) and/or ultraviolet light arranged to pump the luminescent medium, said luminescent medium essentially having a main phase of a solid state host material which is doped with Ce 3+ -ions. According to the invention the host material comprises ions of a further rare-earth material Ln, wherein the host material is selected such that the emission energy of the 5d-4f emission on Ce 3+ -ions is energetically higher than the absorption energy into an upper 4f n state of the further rare-earth material Ln, and wherein the light emission of wavelength converted light is caused by an intra-atomic 4f n - 4f n transition within the ions of the further rare-earth material. The invention further relates to a corresponding lighting system comprising the light-emitting device and a corresponding luminescent medium.

Apparatus for determining a flow property of a fluid

The invention relates to an apparatus (1) for determining a flow property of a fluid (2). The apparatus comprises a distance and velocity determination unit (3) for determining distances of elements of the fluid to the distance and velocity determination unit (3) and for determining velocities of the elements at the same time based on a self- mixing interference signal. The apparatus(1)comprises further a flow determination unit (4) for determining the flow property of the fluid(2)based on at least one of the determined distances and velocities. This allows determining the flow property, even if the fluid (2) is optically thick.

Switchable dual wavelength solid state laser

The present invention relates to a switchable dual wavelength solid state laser with a solid state gain medium (1) which is selected to emit optical radiation at a first wavelength with a first polarization and of at least a second wavelength with a second polarization different from said first polarization when optically or electrically pumped. A polarizing device (7) is arranged within the laser cavity, said polarizing device (7) being adjustable at least between said first and said second polarization. The two end mirrors (2, 3) of the laser cavity are designed to allow lasing of the solid state laser at the first wavelength when the polarizing device (7) is adjusted to the first polarization, and to allow lasing of the solid state laser at the second wavelength when the polarizing device (7) is adjusted to the second polarization. The proposed solid state laser allows an easy switching between two emission wavelengths. The polarizing device (7) is for example realized by a combination of a Pockels cell (8) and a polarizer (9). End mirrors (2, 3) suppress unwanted wavelengths and a beam clump (10) absorbs the radiation not fed-back in the resonator.

Laser device with adjustable polarization

The invention describes a laser device (10) comprising an array (50) of laser emitters (100) and a control unit (200), the array (50) comprises at least a first sub array (110) of laser emitters and a second sub array (120) of laser emitters, wherein the first sub array (110) emits laser light of a first polarization and the second sub array (120) emits laser light of a second polarization being different from the first polarization, and wherein the control unit (200) is adapted to control the first sub array (110) and the second sub array (120) such that the polarization of the laser light emitted by the array (50) can be changed. The invention further describes a sensor device (300) and an optical detection system (400) comprising such a laser device (10). Furthermore, a method of determining the shape of an object by means of the optical detection system (400) is described.

Apparatus for determining a flow property of a fluid

The invention relates to an apparatus (1) for determining a flow property of a fluid (2). The apparatus comprises a distance and velocity determination unit (3) for determining distances of elements of the fluid to the distance and velocity determination unit (3) and for determining velocities of the elements at the same time based on a self- mixing interference signal. The apparatus(1)comprises further a flow determination unit (4) for determining the flow property of the fluid(2)based on at least one of the determined distances and velocities. This allows determining the flow property, even if the fluid (2) is optically thick.

Auf leuchtschirm basierendes laserprojektionssystem

Vertical cavity surface emitting laser and method of producing same

A Vertical Cavity Surface Emitting Laser (VCSEL) comprises a layer stack (12) of semiconductor layers. The layer stack (12) comprises a first layer sub-stack (16) forming a mesa, and a second layer sub-stack (18) adjacent to the mesa in stacking direction of the layer stack (12). The layers of the second layer sub-stack (18) extend beyond the layers of the first layer sub-stack (16) in direction perpendicular to the stacking direction. The semiconductor layers of the layer stack (12) form an optical resonator (22) having a first mirror (24), a second mirror (26, 28, 30), an active region (32) between the first and second mirrors for laser light generation, and an oxide aperture layer (34) forming a current aperture (40). The oxide aperture layer (34) is made from Al_1-xGa_xAs with 0 ≤ x ≤ 0.05. The oxide aperture layer (34) is the last layer of the mesa and immediately adjacent to a first layer of the second layer sub-stack (18), wherein the first layer of the second layer sub-stack (18) is a contact layer (42). A method of producing a VCSEL is disclosed as well.

Diode pumped solid-state laser with improved pump light absorption

For a diode pumped solid-state laser, measures to improve the pump light absorption in anisotropic crystals are proposed. The proposed measures reduce the dependency of the pump light absorption on the diode current and the diode temperature as well as on the detuning of the pump diode from the absorption line. These measures include sending the pump radiation twice through the crystal, placement of the laser crystal in an orientation that does not exhibit the optimum absorption and the use of a retarder.

System und verfahren zum erwärmen von objekten in einer produktionslinie

Diode pumped solid-state laser with improved pump light absorption

For a diode pumped solid-state laser, measures to improve the pump light absorption in anisotropic crystals are proposed. The proposed measures reduce the dependency of the pump light absorption on the diode current and the diode temperature as well as on the detuning of the pump diode from the absorption line. These measures include sending the pump radiation twice through the crystal, placement of the laser crystal in an orientation that does not exhibit the optimum absorption and the use of a retarder.

Verfahren und schaltungsanordnung zum betrieb einer entladungslampe

Vertical cavity surface emitting laser device with monolithically integrated photodiode

The present invention relates to Vertical Cavity Surface Emitting Laser (VCSEL) device (10). The VCSEL device (10) comprises an optical resona- tor (18), a photodiode (34), and an electrical contact arrangement (36, 38, 40). The optical resonator (18) comprises a first distributed Bragg reflector (12), a second distributed Bragg reflector (16), and an active region (14) for light emission. The active region (14) is arranged between the first and second distributed Bragg reflectors (12, 16). The photodiode (34) comprises a light absorption region (20). The electrical contact arrangement (36, 38, 40) is arranged to provide an electrical drive current to electrically pump the optical resonator (18), and to electrically contact the photodiode (34). The active region (14) comprises at least one In x Ga 1- x As layer, wherein 0  x < 1, and the light absorption region (20) comprises at least one In y Ga 1-y As layer, wherein 0< y < 1, and wherein y is greater than x.

Vertical cavity surface emitting laser device with integrated tunnel junction

Method of determining operation conditions of a laser-based particle detector

Vcsel with increased wavelength dependence on driving current

The present invention relates to Vertical Cavity Surface Emitting Laser (VCSEL) (10), which comprises an optical resonator (20) with a first distributed Bragg reflector (12), a second distributed Bragg reflector (16), and an active region (14) for laser emission arranged between the first distributed Bragg reflector (12) and the second distributed Bragg reflector (16). The VCSEL (10) comprises an electrical contact arrangement (32, 34) which is arranged to provide an electrical drive current to electrically pump the optical resonator (20). An additional loss layer (18) arranged in the optical resonator (20) provides optical and/or electrical losses. These additional losses increase the wavelength shift of the VCSEL (10), which wavelength shift is an important parameter for sensor applications that rely on self-mixing interference. The present invention further relates to an optical sensor comprising such a VCSEL and a fabrication method thereof.

Vertical cavity surface emitting laser (vcsel) with improved gain-switching behavior

Diode pumped solid-state laser with improved pump light absorption

For a diode pumped solid-state laser, measures to improve the pump light absorption in anisotropic crystals are proposed. The proposed measures reduce the dependency of the pump light absorption on the diode current and the diode temperature as well as on the detuning of the pump diode from the absorption line. These measures include sending the pump radiation twice through the crystal, placement of the laser crystal in an orientation that does not exhibit the optimum absorption and the use of a retarder.

Green emitting solid-state laser comprising a sesquioxide and/or ceramic material

The invention relates to a green emitting solid-state laser with green emitting transparent material, preferably of the material Y 2 O 3 , Gd 2 O 3 , Lu 2 O 3 , Sc 2 O 3 and Er 3+ and Ho 3+ as doping ions. These materials have been found to be of excellent use for green emitting lasers.

Ceramic non-cubic fluoride material for lasers

The invention relates to a ceramic non-cubic fluoride laser material and methods of its manufacture.

Vertical cavity surface emitting laser device with integrated tunnel junction

VCSELs have a substrate, first and second electrical contacts (ECs), and an optical resonator (OR), having first and second distributed Bragg reflectors (DBRs) and an active layer between the DBRs. The first DBR is between the substrate and the active layer. One of the DBRs has: first and second parts, having different conductivity types, and each with a pair of layers with different refractive indices. A tunnel junction (TJ) is between the parts. The ECs are for electrically pumping the OR such that the TJ is reversely biased during operation of the VCSEL. Either the first DBR includes the parts, having a relative thickness of the second part to a total thickness of the first and second parts between 0.1-0.8, or the second DBR has the parts, the second part being on the TJ facing away from the active layer, and the relative thickness being between 0.15-0.6.

Vertical cavity surface emitting laser (vcsel) with improved gain-switching behavior

The invention describes a Vertical Cavity Surface Emitting Laser (100) comprising at least one mesa, wherein the at least one mesa comprises an active region (120), wherein the active region (120) comprises a number of m active layer structures (121, 125) with m ≥ 2, wherein the active layer structures (121, 125) are electrically connected to each other by means of a tunnel junction (123) arranged between the active layer structures (121, 5 125), wherein the at least one mesa further comprises an optical resonator, wherein the optical resonator comprises a first Distributed Bragg Reflector (130) and a second Distributed Bragg Reflector (136), wherein the active region (120) is arranged between the first and the second Distributed Bragg Reflector (130, 136), wherein the Vertical Cavity Surface Emitting Laser (100) further comprises a first electrical contact (101) and a second electrical contact (105), wherein the first and the second electrical contact (101, 105) are arranged to provide an electrical current to the active region (120), wherein the Vertical Cavity Surface Emitting Laser (100) further comprises an electrical control contact (103), wherein the electrical control contact (103) is arranged to control gain-switched laser emission of the Vertical Cavity Surface Emitting Laser (100) by means of at least 1 up to m-1 active layer structures (121, 125) by means of a current between the electrical control contact (103) and the first electrical contact (101) or the second electrical contact (105). The invention further relates to a time-of-flight sensor module (200) comprising such a VCSEL (100). The invention further relates to a method of controlling gain-switching of the VCSEL (100). The invention finally relates to a related computer program product.

Solid state laser device with reduced temperature dependence

VCSEL mit erhöhter Wellenlängenabhängigkeit von Ansteuerungsstrom

Die vorliegende Erfindung betrifft einen Oberflächenemitter (VCSEL) (10), der einen optischen Resonator (20) mit einem ersten Bragg-Spiegel (12), einem zweiten Bragg-Spiegel (16) und einem aktiven Gebiet (14) zur Laseremission, das zwischen dem ersten Bragg-Spiegel (12) und dem zweiten Bragg-Spiegel (16) angeordnet ist, umfasst. Der VCSEL (10) umfasst eine elektrische Kontaktanordnung (32, 34), die dazu eingerichtet ist, einen elektrischen Ansteuerungsstrom bereitzustellen, um den optischen Resonator (20) elektrisch zu pumpen. Eine zusätzliche Verlustschicht (18), die in dem optischen Resonator (20) angeordnet ist, stellt optische und/oder elektrische Verluste bereit. Diese zusätzlichen Verluste erhöhen die Wellenlängenverschiebung des VCSEL (10), wobei die Wellenlängenverschiebung ein wichtiger Parameter für Sensoranwendungen ist, die auf Eigenmischungsinterferenz angewiesen sind. Die vorliegende Erfindung betrifft ferner einen optischen Sensor, der einen solchen VCSEL umfasst, und ein Fertigungsverfahren für diesen.

Method of manufacturing a part of a color ring and a part of a color ring

Method of manufacturing a part of a color ring and a part of a color ring

A method 200 of manufacturing a (part of) color ring is provided. The color ring converts a color of light emitted by a light emitter into at least one other color. The method (200) comprising the steps of: i) pressing (102) a first ring body of a first granulated precursor comprising a first luminescent material for converting the color of the light of the light emitter into a first one of the at least one other color, and ii) sintering (104) the first ring body for obtaining a first ceramic ring. The color ring comprises at least a segment of the first ceramic ring. Further, the method may comprises the steps of: iii) pressing (208) a second ring body of a second granulated precursor, wherein the first luminescent material is absent, iv) sintering (210) the second ring body for obtaining a second ceramic ring, v) segmenting(206) the first ceramic rings in at least two parts and segmenting (212) the second ceramic ring in at least two parts, and vi) forming (214) at least a part of the color ring by coupling a part of the first ceramic ring and a part of the second ceramic ring.

Integrated waveguide laser for lab-on-a-chip diagnostics

The present invention relates to a detection device for detecting target substances in samples. The device comprises a substrate (1) with at least one planar waveguide laser (2) in or on said substrate (1), said waveguide laser (2) having a gain medium (5) for up-conversion or for down-conversion. A top layer (3) of said waveguide laser (2) forms at least part of a surface of said substrate (1) and allows formation of an evanescent wave in a sample contacting said surface. A structure is applied on said top layer (3) to define an array of probe regions (4) on said top layer (3), said probe regions (4) consisting of a coating of probe materials for sensing said target substances to be detected. The present detection device allows a parallel detection of target substances with a highly integrated design.

Vertical cavity surface emitting laser device with monolithically integrated photodiode

The present invention relates to Vertical Cavity Surface Emitting Laser (VCSEL) device (10). The VCSEL device (10) comprises an optical resona- tor (18), a photodiode (34), and an electrical contact arrangement (36, 38, 40). The optical resonator (18) comprises a first distributed Bragg reflector (12), a second distributed Bragg reflector (16), and an active region (14) for light emission. The active region (14) is arranged between the first and second distributed Bragg reflectors (12, 16). The photodiode (34) comprises a light absorption region (20). The electrical contact arrangement (36, 38, 40) is arranged to provide an electrical drive current to electrically pump the optical resonator (18), and to electrically contact the photodiode (34). The active region (14) comprises at least one In x Ga 1- x As layer, wherein 0  x < 1, and the light absorption region (20) comprises at least one In y Ga 1-y As layer, wherein 0< y < 1, and wherein y is greater than x.

Optically pumped solid-state laser with co-doped gain medium

The present invention relates to a solid-state laser comprising a gain medium (6) of a solid-state host material which is co-doped with Ce3+-ions and ions of a further rare-earth material. The host material is selected such that a lower edge of the 5d band of the Ce3+-ions is energetically higher than an upper lasing state of the ions of the further rare-earth material. This laser can be optically pumped by GaN laser diodes (4) in the wavelength region between 400 and 450 nm and emits laser radiation in the visible wavelength range. With this laser, in particular, a GaN diode laser pumped solid-state laser emitting in the green wavelength region can be realized.

High luminance solid state light source

The present invention relates to a solid-state light source comprising one or several laser diodes (1) emitting a laser beam with a first wavelength, a rotatable support (6) arranged in a beam path of the laser beam and a reflector (4) arranged between the laser diodes (1)and the rotatable support(6). The rotatable support(6) is formed of a ring or of an optically transparent disc mounted to be rotatable around a rotation axis(9) such that the laser beam impinges on a ring-shaped area (7) of the rotatable support(6) during rotation. One or several segments of the ring-shaped area (7) comprise at least one wavelength converting material (8) emitting radiation of a second wavelength upon impingement of the laser beam. The reflector (4) allows the passage of the laser beam through a central portion of the reflector (4), collects the radiation emitted from a location of impingement of the laser beam on the ring-shaped area (7) and directs the collected radiation to an emission direction. The support(6) is mounted in a bearing (10) arranged distant from the rotation axis (9) to allow unhindered passage of the radiation directed by the reflector (4) to the emission direction. The arrangement of the reflector between the laser diodes and the rotatable support and the location of the bearing for the support distant from the rotation axis allow a compact design of the solid state light source in connection with a high luminescent efficiency.

VCSEL zum Erzeugen eines Laserlichts

Vorgeschlagen wird ein VCSEL (1) zum Erzeugen eines Laserlichts aufweisend einen Grundkörper (2) mit einer Kavität (3), die einen in einer Stapelrichtung (4) angeordneten ersten und einen zweiten Braggspiegel (5b) und eine zwischen den beiden Braggspiegeln (5a, 5b) angeordnete aktive Schicht (6) zur Erzeugung von Licht aufweist, wobei der wenigstens erste Braggspiegel (5a) durch einen Bondingprozess auf der aktiven Schicht (6) angebracht ist, einer ersten und einer zweiten Elektrode (7a, 7b) zur Einspeisung von elektrischem Strom in die aktive Schicht (6) und einem auf dem ersten Braggspiegel (5a) angeordneten Emissionsbereich (8) zur Emission des Lichts aus der Kavität (3), einem zwischen den Braggspiegeln (5a, 5b) angeordneten Tunnelkontakt (9) zur Begrenzung eines durch den elektrischen Strom zur Erzeugung des Lichts beaufschlagten Aktivierungsbereichs (10) der aktiven Schicht (6), wobei der Emissionsbereich (8) und der Tunnelkontakt (9) entlang einer parallel zur Stapelrichtung (4) ausgerichteten Propagationsachse (11) des Lichts angeordnet sind, wobei in der Kavität (3) mindestens ein Dissipationsabschnitt (15) entlang der Propagationsachse (11) vorgesehen ist, der einen Teil des Lichts beim Propagieren durch den Dissipationsabschnitt (15) in Wärmeenergie umwandelt, sodass sich der Brechungsindex des Dissipationsabschnitts (15) durch die dabei erzeugte Wärme ändert.

Optically pumped solid-state laser with co-doped gain medium

METHOD FOR INCREASING THE CONTENT OF CE<sp>3+</sp> IN LASER MATERIALS

The invention relates to a method of making Ce 3+ containing laser materials with a fast cooling rate. This has been shown to dramatically increase the absorption rate of the 4f-5d-transition of Ce 3+ within the laser material

Vcsel zum erzeugen eines laserlichts

Vorgeschlagen wird ein VCSEL (1) zum Erzeugen eines Laserlichts aufweisend einen Grundkörper (2) mit einer Kavität (3), die einen in einer Stapelrichtung (4) angeordneten ersten und einen zweiten Braggspiegel (5b) und eine zwischen den beiden Braggspiegeln (5a, 5b) angeordnete aktive Schicht (6) zur Erzeugung von Licht aufweist, wobei der wenigstens erste Braggspiegel (5a) durch einen Bondingprozess auf der aktiven Schicht (6) angebracht ist, einer ersten und einer zweiten Elektrode (7a, 7b) zur Einspeisung von elektrischem Strom in die aktive Schicht (6) und einem auf dem ersten Braggspiegel (5a) angeordneten Emissionsbereich (8) zur Emission des Lichts aus der Kavität (3), einem zwischen den Braggspiegeln (5a, 5b) angeordneten Tunnelkontakt (9) zur Begrenzung eines durch den elektrischen Strom zur Erzeugung des Lichts beaufschlagten Äktivierungsbereichs (10) der aktiven Schicht (6), wobei der Emissionsbereich (8) und der Tunnelkontakt (9) entlang einer parallel zur Stapelrichtung (4) ausgerichteten Propagationsachse (11) des Lichts angeordnet sind, wobei in der Kavität (3) mindestens ein Dissipationsabschnitt (15) entlang der Propagationsachse (11) vorgesehen ist, der einen Teil des Lichts beim Propagieren durch den Dissipationsabschnitt (15) in Wärmeenergie umwandelt, sodass sich der Brechungsindex des Dissipationsabschnitts (15) durch die dabei erzeugte Wärme ändert.

Vertical cavity surface emitting laser with integrated photodiode

A vertical cavity surface emitting laser (VCSEL) emits laser light. The VCSEL has an optical resonator and a photodiode. The optical resonator has: a first mirror, an active region configured to generate laser light, and a second mirror. The active region is arranged between the first mirror and the second mirror. The photodiode is integrated in the optical resonator. The photodiode has: an absorption region having a plurality of absorbing layers configured to absorb the generated laser light. The absorbing layers are arranged spaced apart from one another by a distance d which satisfies the condition: d=(2k−1)λ/(4 m). Where λ is the wavelength of the laser light in the absorption region, and k and m are natural numbers ≥1.

Vertical cavity surface emitting laser and method of producing same

A method of producing a Vertical Cavity Surface Emitting Laser, including providing a layer stack of semiconductor layers including a first mirror, a second mirror, an active region between the first and second mirrors, an Al 1-x Ga x As layer with 0≤x≤0.05, and a contact layer immediately adjacent to the Al 1-x Ga x As layer. The method further includes etching the layer stack to obtain a first layer sub-stack forming a mesa and a second layer sub-stack adjacent to the mesa in a stacking direction of the layer stack. Layers of the second layer sub-stack extend beyond layers of the first layer sub-stack in a direction perpendicular to the stacking direction. The Al 1-x Ga x As layer is used as an etch-stop layer. The method further includes removing an outer part of the Al 1-x Ga x As layer to expose, at least partly, the contact layer, and oxidizing the Al 1-x Ga x As layer to obtain an oxide aperture layer.