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. 29, 2008
Filed:
Feb. 22, 2007
Koji Kato, Saitama, JP;
Koji Kato, Saitama, JP;
PENTAX Corporation, Tokyo, JP;
Abstract
A wide-angle lens system includes a negative front lens group and a positive rear lens group, in this order from the object. The negative front lens group includes a negative first sub-lens group and a positive second sub-lens group, in this order from the object. The positive rear lens group includes cemented lens elements having a positive R1 lens element and a negative R2 lens element, a positive R3 lens element having a convex surface facing toward the image, and a positive R4 lens element, in this order from the object. The wide-angle lens system satisfies the following conditions:−0.8<11<−0.1   (1)0.6<<1.1   (2)