Zoom lens having weak plastic element

Details Zoom lens having weak plastic element Zoom lens having weak plastic element

1993-02-16

1995-06-27

Look, Edward K.

Optical: systems and elements

Lens

With variable magnification

359708, G02B 910

Patent

active

054284805

ABSTRACT:
A zoom lens suitable for an inexpensive camera has a front positive lens group and a rear negative lens group. Both groups move for zooming with the rear negative group providing most of the variation in focal length. The front positive group includes a front negative component and a rear positive component while the rear negative group includes a rear negative component and a weak plastic element having at least one aspheric surface. The plastic element is sufficiently weak that it does not cause variation in focus with normal variations in temperature and relative humidity. All other elements in the zoom lens are glass.

REFERENCES:
patent: 4720179 (1988-01-01), Ito
patent: 4787718 (1988-11-01), Cho
patent: 4818081 (1989-04-01), Ito
patent: 4830476 (1989-05-01), Aoki
patent: 4836660 (1989-06-01), Ito
patent: 4854683 (1989-08-01), Ozawa
patent: 4889416 (1989-12-01), Yamada
patent: 4936661 (1990-06-01), Betensky et al.
patent: 4953957 (1990-09-01), Kobayashi
patent: 4993814 (1991-02-01), Hata
patent: 5162947 (1992-11-01), Ito
patent: 5164859 (1992-11-01), Ito
patent: 5218478 (1993-06-01), Itoh
patent: 5270861 (1993-12-01), Estelle
patent: 5270867 (1993-12-01), Eselle
patent: 5315440 (1994-05-01), Betensky et al.

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