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. 04, 2006
Filed:
Jun. 09, 2003
Mineharu Uchiyama, Kawasaki, JP;
Mineharu Uchiyama, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
An optical disk apparatus of this invention includes a light source, an objective lens which focuses a laser beam output from the light source onto an optical disk, a hologram which divides an overlap region where, of reflected light components from the optical disk, a 0th-order light component and ±1st-order light components that are symmetrical with respect to the 0th-order light component overlap by the diameter of the 0th-order light component and also divides a non-overlap region where the 0th-order light component and ±1st-order light components do not overlap along the diameter and a radius perpendicular to the diameter, and a photodetector which independently detects reflected light components from the regions divided by the hologram.