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. 20, 2013
Filed:
Oct. 07, 2009
Masaki Yamamoto, Osaka, JP;
Hirohisa Yamada, Osaka, JP;
Yasuhiro Harada, Osaka, JP;
Hideharu Tajima, Osaka, JP;
Jun Akiyama, Osaka, JP;
Masaki Yamamoto, Osaka, JP;
Hirohisa Yamada, Osaka, JP;
Yasuhiro Harada, Osaka, JP;
Hideharu Tajima, Osaka, JP;
Jun Akiyama, Osaka, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
An optical information recording medium reproducing apparatusincludes: a signal detecting/extracting sectionextracting, from reproduction signal data, extracted reproduction signal data corresponding to a predetermined data pattern; a calculating circuitcalculating, from the extracted reproduction signal data, a reproducing power control value for controlling laser light reproducing power; and a reproducing power control sectioncontrolling the reproducing power based on the reproducing power control value. The predetermined data pattern is obtained from a space which is sandwiched between marks of λ/2NA or longer and is shorter than λ/4NA and/or a mark which is sandwiched between spaces of λ/2NA or longer and is shorter than λ/4NA. Therefore, even when environmental temperature changes in reproduction, the optical information recording medium reproducing apparatus capable of reproducing a super resolution medium including marks each shorter than λ/4NA optimally controls laser light reproducing power and prevents degradation of reproduction signal quality.