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:
Jul. 11, 2006
Filed:
Jul. 23, 2003
Takanori Maeda, Tsurugashima, JP;
Hiroyuki Ota, Tsurugashima, JP;
Takanori Maeda, Tsurugashima, JP;
Hiroyuki Ota, Tsurugashima, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
An information recording/reproducing apparatus of the invention is equipped with an objective lens, a light source and a variable optical element having a grating which demonstrates a piezo-electric effect by means of an electric field. The light source emits and irradiates a laser beam onto the grating to generate a 0th order diffraction beam and +/− 1st order diffraction beams in accordance with first order diffraction efficiency, and the objective lens converges the 0th diffraction beam and +/− 1st order diffraction beams which are irradiated onto an information recording medium for the purpose of information recording or information reproducing. By controlling an electric field applied to the grating, the first order diffraction efficiency of the grating is adjusted, whereby light beams are generated which have power levels appropriate for various kinds of information recording media.