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. 08, 2017
Filed:
Apr. 08, 2013
Hitachi, Ltd., Tokyo, JP;
Makoto Hosaka, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An optical information recording/reproduction device is capable of appropriately correcting the angle of a reference beam during data reproduction even when a wavelength deviation or an angle deviation in multiplexing and vertical directions of the reference beam occurs in a holographic memory recording medium. The optical information reproduction device has a laser light source that generates a reference beam; an image-capturing unit that detects a diffraction ray to be reproduced from the optical information recoding medium; and an optical detection unit that has at least two light-receiving surfaces and is used for detecting a diffraction ray reproduced by irradiating the reference beam on the optical information recording medium. The device also has a light-shielding unit that shields part of the diffraction ray detected by the optical detection unit; and an error signal calculation unit that generates an error signal from a detection signal outputted by the optical detection unit.