| 摘要 |
PROBLEM TO BE SOLVED: To provide a zoom lens having≥38°half field angle at a wide angle end,≥7.1 times magnification ratio, small number of lenses of nearly 9 and resolution corresponding to an image sensor having 10 to 15 million pixels and capable of satisfactorily correcting chromatic aberration of axis and magnification. SOLUTION: The zoom lens includes a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, an aperture stop S, a third lens group G3 having a positive refractive power, and a fourth lens group G4 having a positive refractive power, which are disposed in order from an object side. The first lens group G1 has a negative lens and a positive lens having a convex surface at an object side, which are disposed in order from the object side. An interval between the first lens group and the second lens group is increased and an interval between the second lens group and the third lens group is decreased when changing a magnification of the zoom lens from a wide angle end to a telephoto end. Parameters are so set that the first lens group and the third lens group are moved from positions at the wide angle end toward positions at object sides thereof, at the telephoto end, and properly set conditions are satisfied. COPYRIGHT: (C)2011,JPO&INPIT |
