Patent ID: 6052225
Filing Date: 2000-04-18
Classification: G02B,G03B

Abstract:
A variable magnification viewfinder comprising, in order from an object side, an objective lens system, an image inverting optical system, and an eyepiece lens system, said objective lens system including, in order from an object side, a negative first lens unit, a negative second lens unit, and a positive third lens unit, wherein a real image formed by said objective lens system is observed through said eyepiece lens system after having been converted into an erecting image by said image inverting optical system, wherein during variation of magnification from a lowest magnification side to a highest magnification side, both said second lens unit and said third lens unit move toward the object side monotonically, wherein an air space between each of the adjacent lens units of said objective lens system changes along with variation of magnification, wherein each of said first lens unit, said second lens unit, and said third lens unit consists of a single lens, and wherein the following condition is satisfied:3.ltoreq.n.ltoreq.5where n represents the number of aspheric surfaces included in said first lens unit, said second lens unit, and said third lens unit.