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, 2013
Filed:
Jul. 22, 2011
Fumitomo Yamasaki, Nara, JP;
Kazuhiro Minami, Osaka, JP;
Yoshiaki Komma, Osaka, JP;
Junichi Asada, Hyogo, JP;
Osamu Kajino, Osaka, JP;
Noriaki Terahara, Osaka, JP;
Toshiyasu Tanaka, Osaka, JP;
Fumitomo Yamasaki, Nara, JP;
Kazuhiro Minami, Osaka, JP;
Yoshiaki Komma, Osaka, JP;
Junichi Asada, Hyogo, JP;
Osamu Kajino, Osaka, JP;
Noriaki Terahara, Osaka, JP;
Toshiyasu Tanaka, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
An objective lens, an optical head, an optical disk apparatus and an information processing apparatus which can suppress deterioration of a focal spot caused by a drop in the diffraction efficiency. Inner and outer circumference areas converge a laser beam, out of laser beams having a wavelength λwhich are diffracted by the inner and outer circumference areas, on a first information recording medium; the inner circumference area and a mid-circumference area converge a laser beam, out of the laser beams having a wavelength λwhich are diffracted by the inner circumference area and the mid-circumference area, on a second information recording medium; and the diffraction efficiency of the laser beam having the wavelength λis greater than the diffraction efficiency of the laser beam having the wavelength λ