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. 12, 2016
Filed:
Feb. 27, 2013
Panasonic Corporation, Kadoma-shi, Osaka, JP;
Katsuhiko Hayashi, Nara, JP;
Yasuhiro Tanaka, Hyogo, JP;
Michihiro Yamagata, Osaka, JP;
Yoshiaki Komma, Osaka, JP;
Abstract
An objective lens element having excellent compatibility with optical discs having different base material thicknesses is provided. The objective lens element has optically functional surfaces on an incident side and an exit side. At least either one of the optically functional surfaces on the incident side and the exit side includes a diffraction portion which satisfies at least either one of the following formulas (1) and (2):θ×θ<0 ('×' represents multiplication)  (1),(sin θ)/λ=−(sin θ)/λ  (2),where