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:
May. 03, 1994
Filed:
Jul. 01, 1992
Applicant:
Inventors:
Mikio Yamamuro, Zushi, JP;
Akihiko Doi, Tokyo, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ; G06F / ;
U.S. Cl.
CPC ...
369124 ; 369120 ;
Abstract
A signal processing circuit for a disk apparatus with an optical head, which causes photodiodes to detect light acquired by irradiating light from a laser diode on a disk that has an address portion and data portion recorded thereon, and performs photoelectric conversion of the light. A level converter alters the level of the signal detected by each photodiode and provides an output signal. A detector detects a level of the output signal by switching time constants between the address portion and data portion. Using a bias corresponding to the detected level, the levels of signals detected by the photodiodes are changed.