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:
Jul. 14, 2015
Filed:
Oct. 14, 2014
Funai Electric Co., Ltd., Osaka, JP;
Futoshi Takeda, Suita, JP;
Funai Electric Co., Ltd., Daito-shi, Osaka, JP;
Abstract
The present invention aims for shortening a time required before the focus control is started. The initial focus position is detected, while the optical disc is not rotated, by making the objective lens approach to the optical disc from the first separation position farther from the optical disc than the focus position. The focus control is performed so that the objective lens tracks the focus position of the data recording layer, while the optical disc is rotated, by making the objective lens approach to the optical disc after the objective lens is returned to the second separation position farther from the optical disc than the first separation position. The initial focus position can be focus position of the data recording layer. The second separation position can be a position farther from the optical disc by a predetermined distance than the initial focus position.