Patent ID: 8896929
Filing Date: 2014-11-25
Classification: G02B

Abstract:
1. A projection zoom lens that substantially consists of six lens groups in which a first lens group having negative refractive power, a second lens group having positive refractive power, a third lens group having negative refractive power, a fourth lens group having positive refractive power, a fifth lens group having negative refractive power, and a sixth lens group having positive refractive power are disposed in this order from a magnification side; wherein the reduction side is made telecentric, wherein the second lens group, the third lens group, the fourth lens group, and the fifth lens group are moved and the first lens group and the sixth lens group are fixed while changing magnification, and wherein conditional expressions (1) and (2) below are satisfied: ft: the focal length of the entire system at the telephoto end fw: the focal length of the entire system at the wide angle end f5: the focal length of the fifth lens group, and f3: the focal length of the third lens group.