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:
Jan. 18, 2005
Filed:
Dec. 17, 2002
Takanobu Higuchi, Tsurugashima, JP;
Takanobu Higuchi, Tsurugashima, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
An optical disk includes a substrate, a reflection layer, an organic dye layer, a protection layer and a cover layer. When recording information on the optical disk by a laser beam, an organic dye expands due to heat generation caused by laser beam radiation. The laser beam passes through the cover layer of the optical disk during recordation. The information is recorded in grooves formed in the substrate. Hardness of a resin substrate side of the optical disk is higher than that of a cover layer side of the optical disk so as to propagate stresses generated by the thermal expansion of the organic dye toward the cover layer. The hardness relationship between the cover layer side and the substrate side should be established at least when the information is recorded on the optical disk. The optical disk can record the information more finely because deformations of the reflection layer are prevented when recording the information.