Extended focus control

Details Extended focus control Extended focus control

2004-05-12

2009-06-16

Wellington, Andrea L (Department: 2627)

Dynamic information storage or retrieval

With servo positioning of transducer assembly over track...

Optical servo system

C369S053280

Reexamination Certificate

active

07548493

ABSTRACT:
An apparatus for scanning a track on a record carrier has a head (41) for providing a beam of radiation and generating at least one sensor signal. The device has a focusing unit for controlling a focusing element to maintain an in-focus position for generating a focused spot on the track. The sensor signal is converted into a displacement signal by a multitude of piecewise converters (42, 43, 44), each converter converting a range of the sensor signal values into a position signal, and selection means (46) for selecting one of the position signals as the displacement signal based on an estimated displacement.

REFERENCES:
patent: 3970935 (1976-07-01), Beery et al.
patent: 4695158 (1987-09-01), Kotaka et al.
patent: 4901300 (1990-02-01), Van Der Zande et al.
patent: 5187699 (1993-02-01), Raaymakers et al.
patent: 5247165 (1993-09-01), Hiruta et al.
patent: 5642340 (1997-06-01), Nomura
patent: 5740138 (1998-04-01), Hoshino et al.
patent: 5864526 (1999-01-01), Le Carvennec
patent: 6314069 (2001-11-01), Ceshkovsky
patent: 6452878 (2002-09-01), Graffouliere
patent: 6538982 (2003-03-01), Van Vlerken et al.
patent: 6584048 (2003-06-01), Tateishi et al.
patent: 6724561 (2004-04-01), Wyman
patent: 6798725 (2004-09-01), Horibe et al.
patent: 1220210 (2002-07-01), None
patent: 07006372 (1995-01-01), None
ISR: PCT/IB04/050641.
Written Opinion: PCT/IB04/050641.

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