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:
Jan. 21, 2014
Filed:
Dec. 08, 2008
Tetsuhiro Sakamoto, Kanagawa, JP;
Jun Nakano, Tokyo, JP;
Takayuki Asahina, Shizuoka, JP;
Etsuo Shibasaki, Tokyo, JP;
Hideo Kawachi, Tokyo, JP;
Tetsuhiro Sakamoto, Kanagawa, JP;
Jun Nakano, Tokyo, JP;
Takayuki Asahina, Shizuoka, JP;
Etsuo Shibasaki, Tokyo, JP;
Hideo Kawachi, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
An information signal area on an information signal recording surface is provided as pits on a mirror in accordance with modulated information data, and is covered with a metal alloy reflective film. Sections that do not include pits corresponding to the information data are provided in the information signal area, and portions of the metal alloy reflective film on the sections are formed as perforated marks corresponding to the information data. In this case, the reproduction signal amplification level of a prepit signal and the reproduction signal amplitude level of a perforated mark signal can be obtained as substantially equal values by adjusting the depth and width of pits and/or adjusting the width and length of perforated marks. Hence, waveform distortion due to a waveform equalization circuit and variations in binary signals due to displacement of the slice level are reduced so that signals can be stably and reliably detected with the same reading apparatus.