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. 26, 2003
Filed:
Jun. 03, 2002
Matsushita Electric Industrial Co., Ltd., Kadoma, JP;
Abstract
An optical information recording medium has a first information layer composed of at least three thin films, which is capable of reflecting a portion of incident light and permitting the passage of a portion of incident light. The optical recording medium also has a second information layer composed of at least four thin films. Information can be recorded on or reproduced from the second information layer with light that has passed through the first information layer. The first and second information layers are separated by a transparent separation layer. The first information layer may be composed of a first dielectric layer, a recording layer and a second dielectric layer, and the second information layer may be composed a third dielectric layer, a second recording layer, a fourth dielectric layer and a reflecting layer.