Discrimination method for optical disc types and optical...

Dynamic information storage or retrieval – Condition indicating – monitoring – or testing – Including radiation storage or retrieval

Reexamination Certificate

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C369S044230, C369S112020

Reexamination Certificate

active

07920450

ABSTRACT:
An optical disc apparatus, which discriminates types of optical discs having different thicknesses of transparent layers by using the same wavelength of laser light, includes an aberration correction unit for correcting spherical aberration, an objective lens for condensing the laser beam onto a recording surface of an optical disc, an actuator for moving the objective lens with respect to the optical disc, a signal detection unit for delivering a focus error signal or a sum light signal, a control unit for controlling the aberration correction unit, the actuator and the signal detection unit. The control unit drives and sets the aberration correction unit so that the laser beam has a predetermined spherical aberration, performs a focus search operation of moving the objective lens to approach the optical disc in a state where the laser beam is projected onto the optical disc, and uses at least one of the focus error signal and the sum light signal delivered from the signal detection unit at a just focus position as an optical disc type discrimination signal.

REFERENCES:
patent: 2002/0150016 (2002-10-01), Yasuda et al.
patent: 2004/0037197 (2004-02-01), Fujiune et al.
patent: 2004/0218497 (2004-11-01), Choi et al.
patent: 2005/0157614 (2005-07-01), Ichimura et al.
patent: 2006/0171275 (2006-08-01), Nishikawa
patent: 2006/0215500 (2006-09-01), Hatanaka et al.
patent: 2006/0239139 (2006-10-01), Kataoka et al.
patent: 2006/0280082 (2006-12-01), Yasukawa
patent: 2008/0002548 (2008-01-01), Jeong
patent: 1 394 782 (2004-03-01), None
patent: 1 770 699 (2007-04-01), None
patent: 1770699 (2007-04-01), None
patent: 2004-127473 (2004-04-01), None
patent: 2006-309809 (2006-09-01), None
patent: 2006-268958 (2006-10-01), None
patent: 2007-012177 (2007-01-01), None
patent: 2007-122850 (2007-05-01), None

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