Optical disk apparatus using focal shift signals to control...

Details Optical disk apparatus using focal shift signals to control... Optical disk apparatus using focal shift signals to control...

2006-03-14

2006-03-14

Nguyen, Hoa T. (Department: 2652)

Dynamic information storage or retrieval

Specific detail of information handling portion of system

Radiation beam modification of or by storage medium

C369S112240, C369S112120

Reexamination Certificate

active

07012875

ABSTRACT:
In the past there has been a problem that on a detection surface the influence of interference causes a defocusing signal to degrade, narrowing the range in which spherical aberration can be stably detected. Accordingly, a diffraction grating is used to focus the inner and outer sides of luminous flux on separate optical detectors before the optical flux is focused on an optical detector and defocusing signals are independently calculated to find the difference therebetween, thereby providing a spherical aberration signal. This makes it possible to detect spherical aberation signals more stably.

REFERENCES:
patent: 5446565 (1995-08-01), Komma et al.
patent: 5652744 (1997-07-01), Freeman et al.
patent: 5717678 (1998-02-01), Akiyama
patent: 5787061 (1998-07-01), Tsuchiya et al.
patent: 5920532 (1999-07-01), Yagi et al.
patent: 6400671 (2002-06-01), Hayashi et al.
patent: 6826133 (2004-11-01), Ichimura et al.
patent: 9-128785 (1997-05-01), None
patent: 11-110768 (1999-04-01), None
patent: 11-195229 (1999-07-01), None
patent: 2000-40237 (2000-02-01), None
patent: 2000-57616 (2000-02-01), None
patent: 2000-215505 (2000-08-01), None
patent: 2001-507463 (2001-06-01), None

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