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:
May. 24, 2005
Filed:
May. 18, 2001
Kazuyoshi Itoh, Hyogo, JP;
Wataru Watanabe, Kyoto, JP;
Tadamasa Toma, Osaka, JP;
Japan Science and Technology Corporation, Kawaguchi, JP;
Abstract
A method for rewriting data in a three-dimensional optical memory element created in glass with ultrashort light pulse includes creating a bit due to a photo-induced contrast in index of refraction inside the glass in three dimensions depending of the strength of a first ultrashort-pulse laser beam. Then, irradiating the bit created in three dimensions with a second ultrashort-pulse laser beam having a lower energy than the strength of the first ultrashort-pulse laser beam while condensing the second ultrashort-pulse laser beam with an optical lens at a point shifted from the bit to be moved by a predetermined distance in an opposite direction from the direction of propagation of the first and second ultrashort pulse laser beams, thereby moving the bit for rewriting.