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:
Mar. 02, 1999
Filed:
Sep. 15, 1997
Mitsuya Okada, Tokyo, JP;
Masatsugu Ogawa, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
Disclosed are an optical information recording medium for recording, reproducing and erasing information by emitting laser light with a wavelength in vacuum of .lambda., which has: a transparent substrate through which the laser light can be transmitted; a high refractive-index layer which is formed on the transparent substrate; a guide groove for tracking which is formed on the high refractive-index layer; and a recording layer which is formed on the guide groove for tracking; wherein a width W of the guide groove for tracking and a refractive index n.sub.a of the high refractive-index layer are so set that the following relation: W>.lambda./(2xn.sub.a) is obtained, and an optical information recording medium for reproducing information by emitting laser light with a wavelength in vacuum of .lambda., which has: a transparent substrate through which the laser light can be transmitted; a high refractive-index layer which is formed on the transparent substrate; a concave-convex pit which is formed on the high refractive-index layer; and a reflection layer which is formed on the concave-convex pit; wherein a width W.sub.p of the concave-convex pit and a refractive index n.sub.a of the high refractive-index layer are so set that the following relation: W.sub.p >.lambda./(2xn.sub.a) is obtained.