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:
Sep. 09, 1986
Filed:
Dec. 15, 1983
Toyoaki Takeuchi, Tokyo, JP;
Ken Ohshima, Tokyo, JP;
Hideyuki Kenjyo, Tokyo, JP;
Yoshiaki Ikeda, Tokyo, JP;
Masaharu Sakamoto, Tokyo, JP;
Olympus Optical Co., Ltd., Tokyo, JP;
Abstract
An optical disk apparatus has an optical disk for recording data into a recording area on an optical disk and reproducing the recorded data from the recording area. The optical disk is provided at the center with a first section with the same reflectivity as that of the recording area and a second section with a different reflectivity from that of the recording area. A photosensor sense detects the first section and produces a signal representing a reflectivity on the first section. The reflectivity data obtained from the signal level is used for controlling a gain of the servo system according to the reflectivity data.