Dynamic information storage or retrieval – With servo positioning of transducer assembly over track... – Optical servo system
Patent
1996-07-30
1998-05-26
Hindi, Nabil
Dynamic information storage or retrieval
With servo positioning of transducer assembly over track...
Optical servo system
369 4429, 369 94, G11B 700
Patent
active
057577447
ABSTRACT:
An optical beam in a scanning device is focused on an information layer of a multi-layer optical record carrier. A focus control circuit keeps the focal point of the beam on the information layer. When the focal point jumps to another information layer, the focus control circuit does not monitor the so-called central aperture signal in order not to depend on the presence of information in the information layers. During the jump the characteristics of the feedback loop of the focus control unit are modified to avoid instabilities in the movement of the focal point during the jump. When the focal point is captured on the designated information layer, the characteristics of the feedback loop are restored.
REFERENCES:
patent: 4023033 (1977-05-01), Bricot et al.
patent: 4724533 (1988-02-01), Ohara et al.
patent: 5189293 (1993-02-01), Leenknegt
patent: 5263011 (1993-11-01), Maeda et al.
patent: 5321676 (1994-06-01), Van Velthoven et al.
patent: 5511057 (1996-04-01), Holtslag et al.
patent: 5608715 (1997-03-01), Yokogawa et al.
patent: 5619371 (1997-04-01), Pontinus
Hindi Nabil
U.S. Philips Corporation
LandOfFree
Optical scanning apparatus for a multi-layer record carrier, inc 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 scanning apparatus for a multi-layer record carrier, inc, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical scanning apparatus for a multi-layer record carrier, inc will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1971611