Device for processing optical information and method of manufacturing a coma correction plate as used in such a device
Опубликовано: 19-06-1984
Автор(ы): Gijsbertus Bouwhuis, Hendrik De Lang
Принадлежит: Philips Gloeilampenfabrieken NV
Реферат: PHN. 9830 13 ABSTRACT: A device for processing optical information is provided comprising a system of optical elements arranged along an optical main axis for guiding a light beam to a radiation-sensitive detection system, in which at least one coma correction plate is provided comprising a sub-strate having a dielectric layer varying in thickness such that the differences in path length in the light beam which are formed by coma in the system of optical elements are at least partly compensated for. A method of manufac-turing such a coma correction plate is provided in which, during vapour deposition of the dielectric layer in a vapour deposition device, a plate-shaped substrate is moved at a constant speed below a template parallel to an axis which is situated in the plane of the template, which template is situated between the vapour deposition source and the substrate and has an aperture, which aperture lies across axis and has an edge whose profile on either side of the axis varies as a third power function of the dis-tance to the axis, the point of intersection of the axis with the part of this edge being taken as zero point.
Optical information reproducing device, optical information recording device, and method for recording optical information
Номер патента: US20110235485A1. Автор: Hideharu Mikami. Владелец: Hitachi Consumer Electronics Co Ltd. Дата публикации: 2011-09-29.