Wide-angle zoom lens

Details Wide-angle zoom lens Wide-angle zoom lens

2007-04-03

2007-04-03

Sugarman, Scott J. (Department: 2873)

Optical: systems and elements

Lens

With variable magnification

C359S680000

Reexamination Certificate

active

11213896

ABSTRACT:
The invention relates to a wide-angle zoom lens system easy to ensure telecentricity particularly suited for digital single-lens reflex cameras. The wide-angle zoom lens system comprises a first group G1of negative power, a second group G2of positive power and a third group G3of positive power. Upon zooming from a wide-angle end to a telephoto end, at least the first group G1and the second group G2move such that a spacing between the first group G1and the second group G2becomes narrow and a spacing between the second group G2and the third group G3becomes wide. The first group G1comprises, in order from its object side, a first lens subgroup SG1aof negative refracting power and a second lens subgroup SG1bof negative refracting power. Upon focusing from a far object point to a near object point, the first lens subgroup SG1aand the second lens subgroup SG1bmove toward the object side with a narrowing spacing between them.

REFERENCES:
patent: 4099846 (1978-07-01), Kawamura et al.
patent: 5801887 (1998-09-01), Sato
patent: 5831773 (1998-11-01), Sato
patent: 6853497 (2005-02-01), Yoneyama

Affiliated with

Also associated with

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

Comments { 0 }

Profile ID: LFUS-PAI-O-3743772