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:
Jan. 18, 2005
Filed:
Apr. 03, 2003
Applicant:
Minoru Murayama, Tokyo, JP;
Inventor:
Minoru Murayama, Tokyo, JP;
Assignee:
PENTAX Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 1514 ; G02B 2102 ;
U.S. Cl.
CPC ...
Abstract
An endoscope objective optical system includes a negative first lens group, a positive second lens group, a positive third lens group, and a negative fourth lens group, in this order from the object. The positive second lens group and the positive third lens group are arranged to move while the object distance is varied without changing the overall length from the first lens group to an imaging plane. Due to this arrangement, the focal length of the endoscope objective optical system is varied while maintaining an in-focus state.