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:
Jun. 24, 2014
Filed:
Mar. 08, 2012
Katsuhiko Hayashi, Nara, JP;
Yasuhiro Tanaka, Hyogo, JP;
Michihiro Yamagata, Osaka, JP;
Yoshiaki Komma, Osaka, JP;
Kazuhiko Ishimaru, Osaka, JP;
Katsuhiko Hayashi, Nara, JP;
Yasuhiro Tanaka, Hyogo, JP;
Michihiro Yamagata, Osaka, JP;
Yoshiaki Komma, Osaka, JP;
Kazuhiko Ishimaru, Osaka, JP;
Panasonic Corporation, Kadoma-shi, JP;
Abstract
An objective lens element which has excellent compatibility with optical discs having different base material thicknesses is provided. An objective lens elementhas optically functional surfaces on an incident side and an exit side. Either one of the optically functional surfaces is divided into an inner partB including a rotational symmetry axis and an outer partF which is a ring-shaped region surrounding the inner partB. On the inner partB, a plurality of discontinuous steps are provided. The plurality of steps change in height in the same direction from the optical axis toward the outer part, and each of the steps causes a constant optical path difference longer than the wavelength λto the first incident light beamand causes a constant optical path difference shorter than the wavelength λto the second incident light beam