Patent ID: 8508853
Filing Date: 2013-08-13
Classification: G02B

Abstract:
1. A projection lens consisting of: a first lens group that is formed of a single negative lens; a second lens group that is formed of three positive lenses and a single negative lens; and a stop, which is disposed between the first lens group and the second lens group or in the second lens group, wherein the first lens group, which is formed of the single negative lens, and the second lens group, which is formed of the three positive lenses and the single negative lens, are arranged in order from a magnification side, wherein the projection lens is telecentric on a reduction side, wherein the single negative lens of the first lens group is formed to have at least one aspheric surface, wherein in the second lens group, first and second positive lenses, each of which has a surface convex toward the reduction side, are arranged in order from the magnification side, wherein at least one of the first and second positive lenses is formed as an aspheric lens, and wherein the following conditional expressions (1) and (2) are satisfied: where f f is a focal length of the whole system, and f wherein the following conditional expression (6) is satisfied: where D D is a total length of the projection lens.