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:
Oct. 03, 2000
Filed:
Oct. 20, 1998
Minemasa Ohta, Yamanashi-ken, JP;
Pioneer Electronic Corporation, Tokyo, JP;
Pioneer Video Corporation, Yamanashi-ken, JP;
Abstract
An optical recording medium comprises a substrate layer formed with a plurality of grooves having a pitch of 0.7-0.9 .mu.m, further with a plurality of prepits located between the grooves and separated from each other at a predetermined interval; a recording layer formed on the substrate layer. The optical recording medium is adapted for recording and reproducing information by directing a laser beam (having a wavelength of 600-700 nm) through an objective lens (having an numerical aperture of 0.55-0.70), further through the substrate layer so as to converge the beam on the recording layer. In particular, the plurality of grooves are different from the plurality of prepits in depth and/or width.