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. 26, 2003
Filed:
Oct. 10, 2001
Syuji Tsukamoto, Tokyo, JP;
TDK Corporation, Tokyo, JP;
Abstract
An optical recording medium, which is suitable for multi-level recording forming a recording mark at multiple stages, is obtained. An optical recording medium, which is constructed in a manner that a recording mark is formed on the recording layer by irradiating a laser beam so as to record information, the recording layer being continuously formed in a relative moving direction to the laser beam with plural virtual recording cells, each of which has an arbitrary unit length and a unit width perpendicular to the unit length in the relative moving direction, plural-stage irradiation times being set with respect to the virtual recording cell so that the irradiation time becomes long successively from the first to final stages, a laser beam power being set in at least one irradiation time of the plural-stage irradiation times so as to intermittently become larger than a predetermined threshold value when the laser beam is irradiated to the virtual recording cell, and recording marks being formed in the virtual recording cell and giving plural-stages different optical reflectance to the virtual recording cell.