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. 24, 2009
Filed:
Jul. 11, 2005
Nobuhiro Kihara, Kanagawa, JP;
Hisayuki Yamatsu, Tokyo, JP;
Megumi Ezura, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
The present invention provides a hologram apparatus for recording an interference fringe of a signal beam and a reference beam having a speckle pattern in a recording area of a hologram recording material. The hologram apparatus includes a speckle pattern generating unit for generating the speckle pattern so that the speckle pattern is different in form in the track direction and the cross-track direction of the recording area. With this configuration, it is possible to perform recording under an increased tolerance in the cross-track direction while securing the shift selectivity necessary in the track direction, and, hence, to easily and stably perform the tracking servo at the time of reproduction.