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:
Aug. 05, 1997
Filed:
Sep. 20, 1995
Nobuhisa Yoshida, Zushi, JP;
Katsumi Suzuki, Tokyo, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
The present invention relates to an optical disk and a method of manufacturing the same, and, more particularly, to an optical disk which can ensure high-density recording and a method of pre-formatting this optical disk. This optical disk has a surface on which data is retrieved with a focused light beam and a light beam spot of a predetermined size is formed by the focused light beam, and comprises a first pit group having a plurality of unit pits of a unit pit length arranged in such a manner that adjoining unit pits are separated from each other with a blank of a first blank length, the blank being smaller than a size of the beam spot, the first blank length being set shorter than the unit pit length, and a second pit group following the first pit group and having a plurality of data pits whose lengths are substantially integer multiples of the unit pit length, the data pits being separated from one another with a blank of a second blank length.