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. 14, 2002
Filed:
Jun. 19, 2000
Applicant:
Inventors:
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B 9/04 ; G02B 3/10 ; G11B 7/00 ;
U.S. Cl.
CPC ...
G02B 9/04 ; G02B 3/10 ; G11B 7/00 ;
Abstract
An optical pickup device which includes an objective lens having a numerical aperture of 0.7 or more collects light emitted from a light source and irradiates an optical recording medium. The objective lens and an antireflection film formed thereon are set so that the intensity of light incident on the outermost rim of the objective lens is 45% or more and 80% or less of the intensity of incident light from the light source to the center of the objective lens. According to the configuration, it is possible to provide an optical pickup device including a high NA objective lens which can suppress a reduction in the light amount at the lens rim.