Patent ID: 8711488
Filing Date: 2014-04-29
Classification: G02B

Abstract:
1. A zoom lens comprising: a first lens group including a lens having negative refractive power and a light path changing member for changing a traveling direction of an incident light beam, said first lens group having negative refractive power as a whole; a second lens group including two lenses, i.e., a lens having positive refractive power and a lens having negative refractive power, and having negative refractive power, as a whole; a third lens group including a stop, a front group lens having positive refractive power, and a rear group lens having negative refractive power arranged in this order, and having positive refractive power as a whole; and a fourth lens group having positive or negative refractive power arranged in this order from an object side, wherein said first lens group and said fourth lens group are fixed, said second lens group moves to the object side after the second lens group moves to an image side, said third lens group linearly moves to the object side upon changing a magnification of the zoom lens from a wide-angle end to a telephoto end, and said second lens group has a focal length f said front group lens having positive refractive power in the third lens group has a focal length f