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. 28, 1987
Filed:
Apr. 19, 1984
Applicant:
Inventors:
Assignee:
Ricoh Company, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 44 ; 369 45 ; 369 46 ;
Abstract
An optical pickup for detecting a distance to an optical disk on which information is optically stored includes a tracking error detecting device for detecting a tracking error by receiving a part of the light reflected from the disk and a focusing error detecting device for detecting the remaining part of the light reflected from the disk, structured such that the tracking error detecting device receives 60% or more of the reflected light.