ZOOM LENS

摘要

PROBLEM TO BE SOLVED: To provide a zoom lens of a small size and high performance which is adequate for a small-sized photographing equipment using a small-sized solid-state imaging device etc., and has a practicable variable power ratio of about 2.5 to 3 times. SOLUTION: The zoom lens has, successively from an object side, at least a first lens group G1 having negative refractive power, a second lens group G2 consisting of a combined lens and having positive refractive power, and is so constituted that, at the time of variable magnification from a wide angle end (W) to a telephoto end (T), the first lens group G1 and the second lens group G2 move respectively, and the spacing between the first lens group G1 and second lens group G2 varies. The zoom lens has a diffraction optical face Gf on a lens face of either of the first lens group G1 and the second lens group G2. When the effective diameter (diameter) of the diffraction optical face Gf is defined as C and the focal length of the entire part of the lens system at the wide angle end as fw, the condition of equation 0.2