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:
Sep. 03, 2002
Filed:
Dec. 23, 1999
Kyohji Hattori, Ebina, JP;
Fumiya Ohmi, Sagamihara, JP;
Kenichi Aihara, Machida, JP;
Katsuyuki Yamada, Mishima, JP;
Yuki Nakamura, Yokohama, JP;
Eiji Noda, Kawasaki, JP;
Michihisa Takahashi, Atsugi, JP;
Yujiro Kaneko, Machida, JP;
Yukio Ide, Mishima, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A method of initializing a phase-change optical information recording medium is provided, using an optical system incorporating a semiconductor laser device. The laser device is characterized by a specified spatial power distribution. In a spatial distribution of the laser power focused on the recording medium, in the direction perpendicular to guide tracks the laser device preferably has less average smaller in both end regions of the spatial distribution, which have each 10% of the width at half maximum of the distribution, than the average in the center region of the full width at half maximum of the distribution.