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:
Feb. 01, 1994
Filed:
Jun. 02, 1992
Tadashi Otsuki, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
A rewritable optical disk has a user recording area in which data is stored in a plurality of sectors, and a written sector flag zone radially separated from the user recording area. The written sector flag includes a plurality of written sector flags, each flag corresponding to one sector in the user recording area. Each written sector flag indicates by its setting whether or not information data has been written in its corresponding sector in the user recording area. The written sector flags are single bits, and are written using error correction. The written sector flags are written in sectors in the written sector flag zone. If a sector is determined to be 'no good' and cannot be used for writing written sector flags, the written sector flags that would be written in the 'no good' sector are written in the next good sector following the 'no good' sector. An apparatus for writing and reading an optical disk with a written sector flag zone reads the written sector flags in the written sector flag zone. A write inhibitor, responsive to the read written sector flags, inhibits writing in a sector indicated as having data written in it. The apparatus is responsive to the write inhibitor and writes information data on the disk in a sector in which writing is not inhibited. The apparatus then writes the written sector flag corresponding to the sector to indicate that information data has been written in the sector.