The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 23, 2013
Filed:
Jan. 05, 2011
Tung-hsu Hsieh, Hsinchu, TW;
Tung-Hsu Hsieh, Hsinchu, TW;
Lite-On It Corp., Taipei, TW;
Abstract
A lens pull-in method is used in a near-field optical accessing system. When a lens is in a far-field range, the lens is driven to approach a surface of an optical disc in an open loop control state. If the lens enters a near-field range, a first GES level is inputted as a set value and the lens is driven in a close loop control state. When the gap error signal decreases to the first GES level, the set value is changed to a second GES level, which is higher than the first GES level. When the gap error signal increases to the first GES level, the set value is changed to a target GES level, so that the gap error signal is maintained at the target gap error signal.