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:
May. 17, 1994
Filed:
Sep. 18, 1992
Sony Corporation, Tokyo, JP;
Abstract
An optical recording medium, typically an optical disc, has a recording region of a laser medium extending thicknesswise thereof, and a reference region positioned radially inwardly of the recording region for emitting reference light. The recording region has pits and lands formed on a surface thereof as representing recorded information. The pits and lands having respective first surfaces parallel to corresponding second surfaces on an opposite surface of the recording region. The first and second surfaces provide different thicknesses of the recording region. When pumping light emitted from a semiconductor laser, for example, is applied to the recording region, the recording region operates as optical resonators between the first and second surfaces for emitting laser signal light of a variable frequency depending on the recorded information. The optical resonators have respective optical axes extending thicknesswise of the recording region.