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. 12, 1989
Filed:
Aug. 17, 1987
Applicant:
Inventors:
Atsushi Saito, Ichikawa, JP;
Takeshi Maeda, Kokubunji, JP;
Hisataka Sugiyama, Kokubunji, JP;
Wasao Takasugi, Higashiyamato, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 59 ; 369111 ; 369 50 ; 369 51 ; 369 47 ; 369 48 ; 369106 ; 369116 ; 369 54 ;
Abstract
A method and an apparatus for recording and reproducing information for use with an optical disk apparatus in which a pit edge recording method is used. According to the pit edge recording method, the leading edge and the trailing edge of a hole pit or a record domain generated during a recording operation are dealt with as information. During the recording, the recording pulse width and the recording power are corrected, and during the reproduction, the variation in the edge position is corrected.