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. 04, 2016
Filed:
Aug. 26, 2014
Kazuyasu Ohashi, Chiba, JP;
Kazuyasu Ohashi, Chiba, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A zoom lens includes a first lens group with a diffraction optical element and having positive refractive power, a second lens group having negative refractive power, a third lens group having negative refractive power, and a fourth lens group having positive refractive power, which are sequentially arranged from an object side to an image side. The second lens group and the third lens group are moved in accordance with zooming between a wide angle end and a telephoto end such that the second lens group is positioned to the object-most side at the wide angle end, and the third lens group is positioned to the image-most side at the telephoto end. At least one of the second lens group and the third lens group includes a negative lens satisfying the conditional expressions: 1.50<nd<1.75; 60.0<νd<75.0; and θ−0.0015×νd<0.2550.