Patent ID: 8228612
Filing Date: 2012-07-24
Classification: G02B

Abstract:
1. A zoom lens comprising, in order from an object side to an image side: a first lens group having a positive refractive power and including lens components which fixed to each other; a second lens group having a negative refractive power and being movable in an optical axis direction to perform at least a zooming; a third lens group having a positive refractive power and including lens components which are fixed to each other; a fourth lens group having a positive refractive power and being movable in the optical axis direction to perform focal position correction and focusing by performing a zooming; and a fifth lens group having a positive refractive power, wherein: the fifth lens group includes a three-element cemented lens having a negative refractive power and a lens group having a positive refractive power, and the zoom lens is configured to satisfy the following conditional expressions (5) and (6): where fm is the focal length of a middle lens in the three-element cemented lens, and νm is the Abbe number of the middle lens of the three-element cemented lens.