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:
May. 17, 2005
Filed:
Aug. 20, 2001
Shuji Narimatsu, Suwa, JP;
Akitaka Yajima, Tatsuno-machi, JP;
Shuji Narimatsu, Suwa, JP;
Akitaka Yajima, Tatsuno-machi, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
The invention provides a zoom lens device that can include lens groups. A third lens group (compensator lens group) can be disposed between two lens groups (a second and a fourth lens groups) forming a variator lens group. The two lens groups (the second and fourth lens groups) forming the variator lens group can be retained by a common variator-lens frame and moved together. Accordingly, a zoom lens device, an optical apparatus, and a projector can be provided in which, even when a plurality of lens groups are assembled, degradation of optical characteristics due to decentering between the lens groups can be prevented.