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. 21, 2008
Filed:
Apr. 28, 2006
Ji-yong Zeng, Beijing, CN;
Guo-fan Jin, Beijing, CN;
Min-qiang Wang, Beijing, CN;
Ying-bai Yan, Beijing, CN;
Ji-Yong Zeng, Beijing, CN;
Guo-Fan Jin, Beijing, CN;
Min-Qiang Wang, Beijing, CN;
Ying-Bai Yan, Beijing, CN;
Tsinghua university, Beijing, CN;
Hon Hai Precision Industry Co., Ltd., Tu-Cheng, Taipei Hsien, TW;
Abstract
A Fourier transform lens system includes a first lens group having positive power, a second lens group having positive power, and a third lens group having negative power, all arranged on a common optical axis in that sequence. The first lens group includes a first positive meniscus lens, and a negative meniscus lens adjacent to the second lens group. The first positive meniscus lens has a concave lens surface facing toward a concave lens surface of the negative meniscus lens. The second lens group includes at least one bi-convex lens. The third lens group includes a second positive meniscus lens adjacent to the second lens group and a bi-concave lens. The second positive meniscus lens has a convex lens surface facing toward the second lens group. The Fourier transform lens system satisfies the following conditions: (1) 0.8<f/f<1.4; (2) −1.3<R/f<−0.7; (3) 0.35<R/f<0.75; and (4) 0.3<R/f<0.7.