Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems
Patent
1989-05-01
1990-05-08
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Photocell controls its own optical systems
369 4411, G01J 120
Patent
active
049240790
ABSTRACT:
An optical scanning apparatus, which includes a radiation source (7) supplying a scaning beam (b.sub.1), an objective system (8) for focusing the scanning beam (b.sub.1) to a scanning spot (S.sub.1) in an information plane (2) to be scanned, and a first diffraction element (9) for deforming the beam reflected by the informatin plane (2) in such a way that a focus-error signal can be derived therefrom. The apparatus also includes a second diffraction element (10) for forming two auxiliary beams (b.sub.2, b.sub.3) by means of which a tracking-error signal can be derived, which second diffraction element has such a size and is arranged at such position that the beams originating from the first diffraction element (9) do not traverse the second diffraction element.
REFERENCES:
patent: 4498159 (1985-02-01), Daimon
patent: 4612437 (1986-09-01), Ohsato
patent: 4733065 (1988-03-01), Hoshi
Coops Peter
de Zoeten Peter
Duijvestijn Adrianus J.
Opheij Willem G.
Van Eck Dirk C.
Eason Leroy
Hsia Sherrie
Moran John Francis
Nelms David C.
U.S. Philips Corporation
LandOfFree
Apparatus for optically scanning an information plane does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus for optically scanning an information plane, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for optically scanning an information plane will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2350778