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. 17, 2012
Filed:
Dec. 18, 2008
Tsutomu Sasamoto, Hino, JP;
Tsutomu Sasamoto, Hino, JP;
Olympus Medical Systems Corp., Tokyo, JP;
Abstract
An objective lens for endoscopes has a front lens unit and a rear lens unit with an aperture stop between them. The front lens unit includes a first lens element with negative refracting power and a second lens element with positive refracting power, and the rear lens unit includes a third lens element with positive refracting power, a cemented lens component of a fourth lens element with positive refracting power and a fifth lens element with negative refracting power. The objective lens satisfies the following conditions:−2<<−0.90.94</(×sin θ)<1.70.86<()/(2×)<1.13where SF is the shape factor of the first lens element; D is a distance from the vertex of the image-side surface of the first lens element to the aperture stop; f is the combined focal length of the entire system; θ is a half angle of view; Dis an actually measured distance from the vertex of the object-side surface of the first lens element to the aperture stop; Dis a distance from the aperture stop to a vertex of the image-side surface of the third lens element; fis the focal length of the first lens element; and fis the focal length of the third lens element.