Patent ID: 9256058
Filing Date: 2016-02-09
CPC Classification: G02B

Claim Text:
1. A zoom lens composed of: an object side lens group having positive refractive power; and an image focusing side lens group having negative refractive power arranged in order from an object side, wherein, the object side lens group comprises, in order from the object side: a first lens group having positive refractive power; and a second lens group having negative refractive power, the image focusing side lens group consists of, in order from the object side: a negative lens group A having negative refractive power; and a negative lens group B having negative refractive power arranged by facing the negative lens group A across an air distance, wherein focusing from infinity to a close object is achieved by moving just the negative lens group A toward an image focusing side and satisfy conditional expressions below: where “β2t”: lateral magnification at a telephoto end of the second lens group in infinity focusing, “βAt”: lateral magnification at a telephoto end of the negative lens group A in infinity focusing, “βBt”: lateral magnification at a telephoto end of the negative lens group B in infinity focusing.