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. 25, 1993
Filed:
Jun. 25, 1991
Applicant:
Inventors:
Toshiki Aoi, Nagano, JP;
Masahiro Shinkai, Chiba, JP;
Assignee:
TDK Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B32B / ;
U.S. Cl.
CPC ...
428 64 ; 428 65 ; 428913 ; 430945 ; 346 / ; 3461351 ; 3692751 ;
Abstract
In an optical recording disk 1 comprising a dye layer 2 formed on a substrate 3 as a light absorbing layer and a reflective layer 4 stacked thereon, tracking servo control is carried out by the push-pull method. To produce normal and accurate tracking error signals, the surface of the dye layer 2 includes depressed and raised sections corresponding to grooves 31 and lands 35 and .DELTA.D which is given by the formula: