An optical head for use in an optical recording apparatus contains a lens element that permits independent setting of the magnification and numerical aperture for a forward optical system and a rearward optical system. The optical head includes a light beam emitting assembly that emits a beam of light...http://www.google.fr/patents/US5602383?utm_source=gb-gplus-shareBrevet US5602383 - Optical apparatus for optically reading and recording information
Optical apparatus for optically reading and recording information
