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:
Apr. 22, 2008
Filed:
Jun. 04, 2004
Fumio Suzuki, Yokohama, JP;
Fumio Suzuki, Yokohama, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A zoom lens system for a microscope includes, in the following order from the object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power. Magnification of the zoom lens system is varied by moving the second lens group and the third lens group. The zoom lens system has an entrance pupil on the object side of the first lens group, and the following conditions are satisfied:−1.3<β2<−0.7−0.1<1/β3<0where β2H is the magnification of the second lens group in the highest magnification state, and β3L is the magnification of the third lens group in the lowest magnification state.