Zoom lens

Details Zoom lens Zoom lens

1998-01-14

1999-06-08

Dang, Hung Xuan

Optical: systems and elements

Lens

With variable magnification

351676, G02B 1318

Patent

active

059108606

ABSTRACT:
A zoom lens includes a first movable lens group having negative power and a second movable lens group having positive power, and an immovable diaphragm provided between the first and second lens groups so as not to move during the zooming operation. The zoom lens satisfies (1) 0.45<f.sub.w /f.sub.2 <0.7, (2) 0.5<f.sub.2 /.vertline.f.sub.1 .vertline.<1.0, and (3) 0.8<D.sub.w /f.sub.2 <1.3, whereby f.sub.w represents the focal length of the entire optical system at the wide-angle extremity, f.sub.1 represents the focal length of the first lens group (f.sub.1 <0), f.sub.2 represents the focal length of the second lens group (f.sub.2 >0), and D.sub.w represents the distance between the diaphragm and the first principal point of the second lens group at the wide-angle extremity.

REFERENCES:
patent: 4406523 (1983-09-01), Sato
patent: 4474436 (1984-10-01), Itoh
patent: 4730906 (1988-03-01), Okudaira
patent: 4973143 (1990-11-01), Ishii et al.
patent: 5331464 (1994-07-01), Itoh

Affiliated with

Also associated with

Rating

Zoom lens does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Zoom lens, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Zoom lens will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1686084