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. 27, 1998
Filed:
Oct. 29, 1997
Applicant:
Inventors:
Assignee:
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ; G02B / ; G02B / ;
U.S. Cl.
CPC ...
359660 ; 359717 ; 359784 ; 359793 ;
Abstract
An objective lens for an endoscope includes a front lens of negative power, an aperture stop, and a rear lens group of positive power in this order from the object side. At least one surface of the front lens group and/or the rear lens group is a compound aspherical lens made of a glass lens and a transparent layer applied to the glass lens surface. A surface of the transparent layer farther from the glass lens is an aspherical surface. The refractive index n of the glass lens to which the transparent layer is applied is more than 1.65 (n>1.65).