Zoom lens system

Details Zoom lens system Zoom lens system

2006-03-28

2006-03-28

Spector, David N. (Department: 2873)

Optical: systems and elements

Lens

With variable magnification

C359S680000, C359S685000

Reexamination Certificate

active

07019912

ABSTRACT:
A zoom lens system includes a negative first lens group, a positive second lens group, and a positive third lens group. Upon zooming from the short focal length extremity to the long focal length extremity, a distance between the negative first lens group and the positive second lens group decreases, and a distance between the positive second lens group and the positive third lens group increases. When zooming is being performed, the negative first lens group remains stationary, and the positive second lens group and the positive third lens group are moveable along the optical axis of the zoom lens system; and the zoom lens system satisfies the following conditions:in-line-formulae description="In-line Formulae" end="lead"?1.5<f3/f2<2.5   (1)in-line-formulae description="In-line Formulae" end="tail"?in-line-formulae description="In-line Formulae" end="lead"?0.8<f2/(fw*ft)1/2<1.3   (2)in-line-formulae description="In-line Formulae" end="tail"?whereinf2designates the focal length of the positive second lens group;f3designates the focal length of the positive third lens group;fw designates the focal length of the entire zoom lens system at the short focal length extremity; andft designates the focal length of the entire zoom lens system at the long focal length extremity.

REFERENCES:
patent: 6040949 (2000-03-01), Ohno
patent: 6246529 (2001-06-01), Sensui
patent: 6515805 (2003-02-01), Hagimori
patent: 6522476 (2003-02-01), Koreeda
patent: 6621642 (2003-09-01), Hagimori
patent: 6781768 (2004-08-01), Minefuji
patent: 2003/0197949 (2003-10-01), Eguchi
patent: 2004/0012859 (2004-01-01), Minefuji
patent: 2004/0051958 (2004-03-01), Yoneyama
patent: 10-206732 (1998-08-01), None
patent: 11-237549 (1999-08-01), None
patent: 2002-14284 (2002-01-01), None
patent: 2002-55278 (2002-02-01), None
patent: 2002-82284 (2002-03-01), None
U.S. Appl. No. 10/929,364 to Saori, which was filed on Aug. 31, 2004.
U.S. Appl. No. 10/940,704 to Eguchi, which was filed on Sep. 15, 2004.

Affiliated with

Also associated with

Rating

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

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3583456