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:
Feb. 28, 1995
Filed:
Sep. 03, 1993
Takefumi Sakurada, Akishima, JP;
Naoaki Tani, Hachioji, JP;
Takumi Sugaya, Hachioji, JP;
Takao Rokutan, Higashimurayama, JP;
Mitsuo Oshiba, Hachioji, JP;
Akira Shirai, Hino, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
A beam-spot control unit is arranged such that a light beam is irradiated onto an optical recording medium having a plurality of tracks, through an objective lens, to detect reflecting light of beam spots formed on the tracks by three or more photo detecting elements which are arranged in a direction corresponding to a track transverse direction. From a tracking error signal which is generated by a difference signal of pairs of photo detecting elements which are selected by a selecting switch from these photo detecting elements, a control signal is generated which positions the beam spots to a plurality of recording lines within a single track. A tracking control mechanism is utilized to enable positioning of the beam spots to a plurality of recording lines within the single track to be performed.