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. 12, 2008
Filed:
Feb. 08, 2006
Kazunori Ito, Yokohama, JP;
Hajime Yuzurihara, Odawara, JP;
Nobuaki Onagi, Yokohama, JP;
Katsuyuki Yamada, Zama, JP;
Shinya Narumi, Yokohama, JP;
Kazunori Ito, Yokohama, JP;
Hajime Yuzurihara, Odawara, JP;
Nobuaki Onagi, Yokohama, JP;
Katsuyuki Yamada, Zama, JP;
Shinya Narumi, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A phase-change optical information recording medium in which information can be recorded, reproduced and rewritten and which includes a first transparent substrate having a wobbling guide groove which is spirally formed thereon at a pitch; a first dielectric layer located overlying the first transparent substrate and having an optical thickness of from 80 nm to 200 nm; a phase-change recording layer located overlying the first dielectric layer and having an optical thickness of from 20 to 50 nm when the recording layer is in an erased state; a second dielectric layer located overlying the recording layer and having an optical thickness of from 10 nm to 70 nm; a reflection layer located overlying the second dielectric layer; optionally a third dielectric layer located between the second dielectric layer and the reflection layer; and a second transparent substrate located overlying the reflection layer.