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:
Mar. 13, 1990
Filed:
Sep. 19, 1988
Akira Gotoh, Toride, JP;
Yukinobu Yamazaki, Ibaragi, JP;
Naoyuki Kikuchi, Toride, JP;
Shinkichi Horigome, Tachikawa, JP;
Motoyasu Terao, Tokyo, JP;
Hiroyuki Suzuki, Ibaragi, JP;
Makoto Kitoh, Yokohama, JP;
Yuichi Kokaku, Yokohama, JP;
Mitsuru Shimizu, Toride, JP;
Hitachi Maxell, Ltd., Osaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In an optical recording medium, an under layer is formed between an even pattern of a substrate and a recording layer, and said under layer is made of a high polymeric material which can be melted, sublimated, or decomposed at a lower temperature than the melting point, the sublimating point, or the decomposing temperature of said recording layer. Accordingly, said under layer can relax the thermal shock transferred from said substrate into said recording layer, and the deformation of said substrate can be prevented, even through a laser beam for playback is repeatedly radiated onto said recording layer, and said optical recording medium has a larger recording sensitivity than the recording sensitivity of an optical recording disc of a prior art.