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:
Dec. 26, 1995
Filed:
Aug. 19, 1994
Hitachi, Ltd., Tokyo, JP;
Hitachi Maxell, Ltd., Tokyo, JP;
Abstract
An information recording medium has a thin-film recording layer and a reflective layer that reflects a laser beam. The recording layer can be composed of an inorganic substance whose optical constant changes when exposed to a laser beam due to the change of its atomic arrangement. The recording layer can also be of an organic substance that deforms when exposed to a laser beam. The medium reflectivity, with respect to the reproduction laser beam exposure from the substrate side, is at least 65 percent on either of the recorded and unrecorded marks, and not more than 45 percent from the other of the recorded and unrecorded marks. In addition, the reflective-layer reflectivity, with respect to the reproduction laser beam, is at least 85 percent. The information recording medium additionally features excellent recording, erasing, and reproduction characteristics, with low recording power and high recording sensitivity during recording, and can even be read by a CD drive or the like.