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:
Nov. 10, 2015
Filed:
Feb. 01, 2011
Takumi Iba, Kyoto, JP;
Takashi Kitamura, Osaka, JP;
Masatoshi Yamashita, Osaka, JP;
Hirohiko Ina, Hyogo, JP;
Takumi Iba, Kyoto, JP;
Takashi Kitamura, Osaka, JP;
Masatoshi Yamashita, Osaka, JP;
Hirohiko Ina, Hyogo, JP;
Abstract
The present invention provides an image pickup lens with a large focal depth from the center to the outer part of an image plane formed on an image sensor and capable of maintaining its focal depth within a practical range and thus suppressing a decline in the resolution. An image pickup lensincludes, in order from the object side to the image plane side, an aperture stop, a first lensthat is a biconvex lens having positive power, a second lensthat is a meniscus lens having negative power and whose lens surface facing the object side is convex, a third lensthat is a meniscus lens having positive power and whose lens surface facing the object side is concave, and a fourth lensthat is a biconcave lens having negative power. The image pickup lensincludes a multifocal lens on the lens surface of the first lensfacing the object side. D and Ymax satisfy the following conditional expression ():0max≦0.1  (1)where D is an absolute value of the distance between the multifocal lens surface and a surface of the aperture stop on the optical axis, and Ymax is the absolute value of the maximum image height on an image plane formed on the image sensor.