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. 18, 1992
Filed:
Apr. 14, 1989
Applicant:
Inventors:
Assignee:
Taiyo Yuden Co., Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369284 ; 3692754 ;
Abstract
An optical information recording medium comprising a light transmitting substrate, a light absorptive layer overlaying the substrate to absorb a laser beam and a light reflective layer overlaying the light absorptive layer, wherein an optical parameter represented by .rho.=n.sub.abs d.sub.abs /.lambda. where n.sub.abs is the real part of the complex refractive index of the light absorptive layer, d.sub.abs is the thickness of the light absorptive layer and .lambda. is the wavelength of a reading laser beam, is 0.05.ltoreq..rho..ltoreq.0.6, and the imaginary part k.sub.abs of the complex refractive index of the light absorptive layer is at most 0.3.