Zoom lens

Details Zoom lens Zoom lens

2010-11-24

2011-12-20

Lester, Evelyn A. (Department: 2873)

Optical: systems and elements

Lens

With variable magnification

C359S683000, C359S684000, C359S685000

Reexamination Certificate

active

08081392

ABSTRACT:
The invention relates to a new mechanism for permitting a zoom lens to focus on a short distance subject by moving a focusing lens group in an amount that varies in an optical axis direction depending on a zooming position. The zoom lens comprises, in order from its object side, a positive first lens group, a negative second lens group and a positive third lens group. Zooming is implemented while the space between adjoining lens groups is varied, and focusing on a short distance subject is implemented by moving the negative second lens group in an amount that varies in the optical axis direction depending on a zooming position. The negative second lens group comprises a negative front unit G2F and a negative rear unit G2R. The space between the negative front unit G2F and the negative rear unit G2R is varied depending on a subject distance but that space remains constant wherever the zooming position lies.

REFERENCES:
patent: 5666230 (1997-09-01), Tatsuno
patent: 7061700 (2006-06-01), Honsho
patent: 2002/0114083 (2002-08-01), Cheung
patent: 2003/0035224 (2003-02-01), Nishimura et al.
patent: 2003/0202262 (2003-10-01), Sasaki et al.
patent: 2005/0007680 (2005-01-01), Naganuma et al.
patent: 2004-341060 (2004-12-01), None

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-4299299