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:
Oct. 23, 2012
Filed:
Oct. 17, 2006
Tetsuya Ogata, Yokohama, JP;
Tetsuya Ogata, Yokohama, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An extraction optical system for use in an optical pick-up device receiving a reflected light from an optical disc having a plurality of recording layers is provided. The extraction optical system extracts from a light in which a signal light component from an access target recording layer of the plurality of recording layers and a stray light component from a recording layer other than the access target recording layer of the plurality of recording layers are mixed, the signal light component from the access target recording layer of the plurality of recording layers. The extraction optical system includes a condensing optical element arranged in an optical path of the light and condensing the light, and a selective optical system to which the light condensed by the condensing optical element is incident and reflecting a light primarily containing the signal light component.