Patent Number: 6,310,732

Title: Simple power-variable finder

Abstract: A small-size, inexpensive, simple power-variable finder comprises, successively from the object side, a negative first lens group G.sub.1, a positive second lens group G.sub.2, and a negative third lens group G.sub.3. As the second lens group G.sub.2 is moved along the optical axis X, zooming is carried out. Field masks M.sub.1 to M.sub.3 are disposed at predetermined positions. The finder satisfies the following conditional expressions (1) to (3): where f.sub.i is the focal length of the i-th lens group, and D.sub.T is the distance on the optical axis between the surface closest to the object in the first lens group G.sub.1 and the surface closest to an eye in the third lens group G.sub.3.

Inventors: Ohno; Kazunori (Omiya, JP)

Assignee: Fuji Photo Optical Co., Ltd.

International Classification: G02B 15/177 (20060101); G02B 23/14 (20060101); G02B 015/14 ()

Expiration Date: 10/30/2018