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:
Feb. 28, 2006
Filed:
Oct. 01, 2003
Kaoru Yamamoto, Tsurugashima, JP;
Keiji Suga, Tsurugashima, JP;
Noriyoshi Shida, Tsurugashima, JP;
Tetsuya Iida, Tsurugashima, JP;
Kaoru Yamamoto, Tsurugashima, JP;
Keiji Suga, Tsurugashima, JP;
Noriyoshi Shida, Tsurugashima, JP;
Tetsuya Iida, Tsurugashima, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
Preformatted areas in at least the most distal recording layer from an object lens among a plurality of recording layers in an optical disc include guard areas at both ends of the respective recording layer in the tracing direction. No data is recorded on the guard areas. The guard area length GL is determined to satisfy the following formula:×()/[1−()]where YL is a maximum allowable value of position deviation between the preformatted areas in the most distal recording layer and in another recording layer in the tracing direction; NA is the numerical aperture of the object lens; T is a distance between the most distal and the another recording layer; and 'n' is an refraction index of a medium between the most distal and the another recording layers.