Dynamic information storage or retrieval – Specific detail of information handling portion of system – Radiation beam modification of or by storage medium
Patent
1996-02-27
1996-11-26
Hindi, Nabil Z.
Dynamic information storage or retrieval
Specific detail of information handling portion of system
Radiation beam modification of or by storage medium
369109, G11B 700
Patent
active
055792987
ABSTRACT:
A device for optically scanning an information plane (2) having tracks (5). Radiation supplied by a radiation source (7) is focused on the information plane by an objective system (8). The beam reflected by the information plane is incident on a dividing element, for example, a grating (12), which divides the beam into two halves along a dividing line (17). Two sub-gratings (15, 16) at both sides of the dividing line, respectively, each form a sub-beam from one half of the beam, which sub-beams are detected by a detection system (10), which produces detection signals therefrom. A focus error signal is generated from the detector signals. According to the invention, modulation of the focus error signal by the track structure will be minimal if the dividing line (17) is located at an angle between 15.degree. and 80.degree. to the direction of the tracks.
REFERENCES:
patent: 4665310 (1987-05-01), Heemskerk
patent: 4724533 (1988-02-01), Ohara et al.
patent: 4733065 (1988-03-01), Hoshi et al.
patent: 4829506 (1989-08-01), Bressers et al.
patent: 4945529 (1990-07-01), Ono et al.
patent: 5036504 (1991-07-01), Ono et al.
patent: 5062098 (1991-10-01), Hori et al.
patent: 5065380 (1991-11-01), Yokota
patent: 5111449 (1992-05-01), Kurata et al.
patent: 5231620 (1993-07-01), Ohuchida
patent: 5253237 (1993-10-01), Miyake et al.
patent: 5270996 (1993-12-01), Ono
patent: 5391865 (1995-02-01), Kurata et al.
Benschop Jozef P. H.
Opheij Willem G.
Steinhauser Heidrun
Hindi Nabil Z.
U.S. Philips Corporation
Weiss Richard A.
LandOfFree
Optical scanner having symmetry about an oblique divider does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Optical scanner having symmetry about an oblique divider, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical scanner having symmetry about an oblique divider will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1978726