An optical head which uses a single diffraction grating to eliminate the need for both a beam-splitter and a biprism lens. This invention allows the placement of all the elements except the photodetector along a single optical axis with the photodetector immediately adjacent to the optical axis. This...http://www.google.es/patents/US4794585?utm_source=gb-gplus-sharePatente US4794585 - Optical head having a hologram lens and polarizers for use with magneto-optic medium
Optical head having a hologram lens and polarizers for use with magneto ...
