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. 20, 2001
Filed:
Apr. 27, 1999
Shuichi Okubo, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A phase-changing optical disk solving the problem of difference in recording sensitivity between the land and groove without complexing configuration of the recording device or optical disk production scheme. The present invention provides a phase-changing optical disk including a substrate,provided with guiding grooves,to form the lands and grooves as the recording tracks, which are laminated with a first dielectric layer,second dielectric layer,recording layer,third dielectric layer,and reflection layer,in this order, wherein the material for the first dielectric layer,has a higher thermal conductivity than that for the second dielectric layer,and thickness of the second dielectric layer,is smaller than depth ds of the guiding groove,This accelerate thermal diffusion H,from the both ends of the groove toward the first dielectric layer,decreasing recording sensitivity of the groove to a level of the land, thermal diffusion H,from which would be otherwise larger than H