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. 15, 2005
Filed:
Feb. 19, 2003
Hidekazu Totsuka, Hachioji, JP;
Shinichiro Saito, Hachioji, JP;
Katsuya Sakamoto, Hachioji, JP;
Kiyono Ikenaka, Hino, JP;
Hidekazu Totsuka, Hachioji, JP;
Shinichiro Saito, Hachioji, JP;
Katsuya Sakamoto, Hachioji, JP;
Kiyono Ikenaka, Hino, JP;
Konica Corporation, Tokyo, JP;
Abstract
An objective optical element for use in an optical pickup apparatus, includes an objective lens to converge the light flux emitted from the first and second light sources; and an optical functional surface including a common region and an exclusive region. When a first optical information medium is used, a sine condition unsatisfied-amount whose value is maximum exists on the common region. The following formula is satisfied:0.5≦COMA2/COMA1≦1.0where COMA1 is a coma aberration (λ1 rms) when a light flux goes slantingly to be incident with a view angle of 1° onto the objective optical element when the first optical information medium is used, and COMA2 is a coma aberration (λ2 rms) when a light flux goes slantingly to be incident with a view angle of 1° onto the objective optical element when the second optical information medium is used.