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:
Apr. 30, 2002
Filed:
May. 05, 2000
Applicant:
Inventors:
Kazutaka Abe, Kitakatsuragi-gun, JP;
Tetsuo Iwaki, Yamatokoriyama, JP;
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/00 ;
U.S. Cl.
CPC ...
G11B 7/00 ;
Abstract
Thickness information and refractive index information of a light transmitting layer are recorded in advance on an optical recording medium. Based on the thickness information and the refractive index information of the light transmitting layer, space between two lens units of an objective lens system is adjusted in an optical recording and reproducing apparatus, so that spherical aberration is adjusted. Accordingly, in the optical recording and reproducing apparatus using two lens units, it becomes possible to correctly record or reproduce the information to and from the optical recording medium.