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. 11, 2004
Filed:
Jun. 14, 1999
Guo-Fu Zhou, Eindhoven, NL;
Roel Van Woudenberg, Eindhoven, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
A description is given of a disc-shaped rewritable optical information medium having an IPIM stack ( ) comprising a phase-change recording layer ( ) sandwiched between two dielectric layers ( ), and a metal mirror layer ( ). The thickness of the recording layer ( ) increases gradually with increasing radius r. As a result, the complete erasure time CET of recorded marks decreases from the inner radius r to the outer radius r . Therefore, at a point closer to the outer radius marks can be recorded at a higher linear speed than at a point closer to the inner radius. This effect ensures that the recording medium can be used for recording at a constant angular velocity (CAV).