Dynamic information storage or retrieval – With servo positioning of transducer assembly over track... – Optical servo system
Reexamination Certificate
2007-05-01
2007-05-01
Korzuch, William (Department: 2627)
Dynamic information storage or retrieval
With servo positioning of transducer assembly over track...
Optical servo system
C369S053280, C369S044250
Reexamination Certificate
active
10682040
ABSTRACT:
A method and device are provided for adjusting a focus bias of an objective lens of an optical pickup for an optical disc using a level of a tracking error signal. The level of the tracking error signal outputted when the optical disc is rotated and driven is detected for a predetermined period of time. An operation of adjusting the focus bias of the objective lens is carried out on the basis of the detected level of the tracking error signal. A focus bias adjustment value is set as an optimum focus bias value at a time when the detected level of the tracking error signal is maximized. In accordance with the method, a period of time for adjusting the focus bias is very short, on the order of “0” to several hundred milliseconds, in comparison with periods of time for adjusting the focus bias in conventional methods, such that the focus bias can be quickly adjusted. Moreover, the method moves the objective lens to an optimum focus point where the thickness of a substrate in the optical disc is thinner or thicker than the standard thickness (e.g., 0.6 mm in the case of a DVD (Digital Versatile Disc)), thereby enabling a normal playback operation.
REFERENCES:
patent: 4707648 (1987-11-01), Minami
patent: 5218588 (1993-06-01), Suzuki
patent: 5612939 (1997-03-01), Ueki et al.
patent: 5627807 (1997-05-01), Abe
patent: 5808983 (1998-09-01), Tsutsui et al.
patent: 2002/0110057 (2002-08-01), Kadlec et al.
Kim Dong Sik
Kim Kyung Soo
Seo Seong Hwan
Birch & Stewart Kolasch & Birch, LLP
Korzuch William
Lamb Christopher
LG Electronics Inc.
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