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:
Jul. 15, 1997
Filed:
Sep. 22, 1994
Takaomi Sekiya, Tokyo, JP;
Moriyasu Shirayanagi, Tokyo, JP;
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
The present invention provides methods and apparatuses to evaluate the best image plane position for an optical lens system, particularly a wide angle lens with a large power ratio, in e.g. an endoscope, in simple and less time consuming procedure. The present devices and methods include a screen which can form an edge image, an optical system which forms an image of the screen, a light receiver located at the focal plane, or in its neighborhood, on which the edge image of the screen is formed by the optical system to convert the edge image into an electric signal, and a sampler which samples the electric signal transmitted from the light receiver in a crossing direction perpendicular to the edge image.