Patent ID: 9097879
Filing Date: 2015-08-04
Classification: G02B

Abstract:
1. A zoom lens consisting of three lens groups including, in order from an object side, a first lens group having a negative refractive power, a second lens group having a positive refractive power and a third lens group having a positive refractive power, wherein, during magnification change from a wide-angle end to a telephoto end, at least the first lens group and the second lens group are moved along an optical axis such that an interval between the first lens group and the second lens group is decreased and an interval between the second lens group and the third lens group is increased, the second lens group consists of, in order from the object side, a second-group first lens having a positive refractive power, a cemented lens consisting of a second-group second lens having a positive refractive power and a second-group third lens having a negative refractive power, a second-group fourth lens having a positive refractive power, and a second-group fifth lens having a negative refractive power, and the conditional expressions (1) and (2) below are satisfied: where fw is a focal length of the entire lens system at the wide-angle end, f