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. 14, 2012
Filed:
Jul. 24, 2007
Masaki Yamamoto, Nara, JP;
Hirohisa Yamada, Tenri, JP;
Toshihiko Sakai, Nara, JP;
Yasuhiro Harada, Nara, JP;
Go Mori, Nara, JP;
Hideharu Tajima, Nara, JP;
Masanori Shimo, Gose, JP;
Nobuyuki Takamori, Nara, JP;
Masaki Yamamoto, Nara, JP;
Hirohisa Yamada, Tenri, JP;
Toshihiko Sakai, Nara, JP;
Yasuhiro Harada, Nara, JP;
Go Mori, Nara, JP;
Hideharu Tajima, Nara, JP;
Masanori Shimo, Gose, JP;
Nobuyuki Takamori, Nara, JP;
Sharp Kabushiki Kaisha, Osaka-Shi, Osaka, JP;
Abstract
In an optical information recording medium (), a light-transmitting layer () or a transparent substrate, an information recording layer (), and a substrate () are stacked in this order from a side from which reproducing light () enters. The information recording layer () includes at least a reproducing film () whose complex refractive index at a light source wavelength (λ) of the reproducing light () is changed by heat. The relationship of 0.67×(λ/NA)>TP>0.04×(λ/NA) is satisfied, where TP is a track pitch of prepits () formed on the substrate (), and NA is a numerical aperture of an objective lens () for converging the reproducing light () on the optical information recording medium.