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:
Jun. 20, 1989
Filed:
Dec. 17, 1986
Applicant:
Inventors:
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 54 ; 369 58 ; 369106 ; 369116 ;
Abstract
An optical disk apparatus is disclosed in which data is recorded, reproduced and erased on an erasable optical disk. After first data is recorded in a predetermined track or sector, it is erased. Second data is then recorded in the same track or sector, and it is decided that the erase function is normal when the second data is reproduced correctly.