Wide-angle zoom lens

Optical: systems and elements – Lens – With variable magnification

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

359683, G02B 1514

Patent

active

057241929

ABSTRACT:
A wide-angle zoom lens system which can reduce variation in aberrations and obtain a sufficient back focus distance at the wide angle position by making the view angle wide at the wide angle position and making the whole length of the optical system short at the telephoto position. The wide-angle zoom lens system, includes a first lens group having a positive refractive power; a second lens group having a positive refractive power; and a third lens group having a negative refractive power, the distances between the first lens group, the second lens group, and the third lens group change during zooming, wherein the first lens group includes a first lens having a negative refractive power with a shape of a meniscus lens concave toward an object, a second lens having a positive refractive power and a third lens having a negative refractive power, the first, second and third lens groups are made of spherical lenses, the distance between the first and second lens groups is increased, and the distance between the second and third lens groups is reduced; and wherein the zoom lens system has the following characteristics: -0.5<(R.sub.1a1 +R.sub.1a2) / (R.sub.1a1 -R.sub.1a2)<-2.0 wherein R.sub.1a1 is a curvature radius toward the object of a lath lens in the first lens group, and R.sub.1a2 is the curvature radius toward the image plane of the lath lens in the first lens group.

REFERENCES:
patent: 5315439 (1994-05-01), Ito
patent: 5528429 (1996-06-01), Hagimori
patent: 5530593 (1996-06-01), Shibayama et al.
patent: 5566026 (1996-10-01), Yoon

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Wide-angle 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 Wide-angle zoom lens, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Wide-angle zoom lens will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2254163

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.