Patent ID: 9696527
Date: 2017-07-04
CPC Classifications: G02B

Claim:
1. A projection lens comprising a first lens group and a second lens group, all of which are arranged in sequence from a projection side to an image source side along an optical axis, wherein: the first lens group is with positive refractive power and comprises a fifth lens and a sixth lens, both of which are arranged in sequence from the projection side to the image source side along the optical axis, wherein the fifth lens is with negative refractive power and the sixth lens is with positive refractive power; the second lens group is with positive refractive power and comprises a first lens, a second lens, a third lens and a fourth lens, all of which are arranged in sequence from the projection side to the image source side along the optical axis, wherein the first lens is with negative refractive power, the second lens is with positive refractive power, the third lens is with positive refractive power and the fourth lens is with positive refractive power; the first lens and the second lens are cemented together to form a cemented lens, and the cemented lens is with negative refractive power; and the projection lens satisfies: wherein TTL is a distance from a projection side surface of the first lens group to an image source along the optical axis and f is an effective focal length of the projection lens.