Dynamic information storage or retrieval – With servo positioning of transducer assembly over track... – Optical servo system
Reexamination Certificate
2007-02-13
2007-02-13
Hindi, Nabil (Department: 2627)
Dynamic information storage or retrieval
With servo positioning of transducer assembly over track...
Optical servo system
C369S053180, C369S053420
Reexamination Certificate
active
10795295
ABSTRACT:
The present invention relates to a track access apparatus and a method by which an optical pick-up unit quickly accesses a destination track of an optical disc by controlling a tracking actuator using a back electromotive force by detecting the vibration of an objective lens, the position variation, and the distortion of an actuator which occur when the optical pick-up unit is moved across the tracks of the optical disc at a high speed. In the present invention, there are provided a photodetector for detecting the amount of the beams of a side spot and a main beam spot based on two sub-beams and one main beam, a differential amplifier for differentiating the two signals of the sub-beams and outputting a tracking error signal, a first phase/gain compensation unit for compensating the phase and gain of the tracking error signal, a position detection unit for detecting the position of the objective lens from two signals of the main beam, a second phase/gain compensation unit for compensating the phase and gain of the lens position detection signal, a microcontroller for outputting a switch control signal, a switch for selecting an output of a first or second phase/gain compensation unit based on the switch control signal, a power amplifier for amplifying the output of the switch, and a tracking actuator for driving the objective lens in the track direction and the radial direction of the tracks.
REFERENCES:
patent: 4764911 (1988-08-01), Morota et al.
patent: 5442604 (1995-08-01), Osada
patent: 5768226 (1998-06-01), Ogino
patent: 5777960 (1998-07-01), Ohno
patent: 5835459 (1998-11-01), Takahara et al.
patent: 5862113 (1999-01-01), Tsuyuguchi et al.
patent: 5909414 (1999-06-01), Ohta
patent: 5920528 (1999-07-01), Ohshima et al.
patent: 5933397 (1999-08-01), Yamashita et al.
patent: 6028826 (2000-02-01), Yamamoto et al.
patent: 6044050 (2000-03-01), Kuroiwa
patent: 6081491 (2000-06-01), Ota et al.
patent: 6141305 (2000-10-01), Tsutsui
patent: 6175540 (2001-01-01), Kim
patent: 6185171 (2001-02-01), Bassett et al.
patent: 6229773 (2001-05-01), Chou
patent: 6243335 (2001-06-01), Choo
patent: 6249495 (2001-06-01), Okada et al.
patent: 6256275 (2001-07-01), Eguchi et al.
patent: 6266301 (2001-07-01), Morimoto
patent: 7-272294 (1995-10-01), None
patent: 9-97439 (1997-04-01), None
Jin Cheol
Lee Dong Keun
Youn Jeong Chae
Birch, Stewart, Kolasch and Birch LLP
Hindi Nabil
LG Electronics Inc.
LandOfFree
Optical disc track access apparatus and method for optical... 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 disc track access apparatus and method for optical..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical disc track access apparatus and method for optical... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3846462