PROJECTION LENS

摘要

A projection lens for a projection device having a light valve is provided. The light valve provides an image light beam. The projection lens includes a first lens group, a second lens group and a reflecting lens group. The second lens group is disposed between the first lens group and the reflecting lens group. The first lens group has positive refractive power. The second lens group has positive refractive power and includes a plurality of lenses and an aperture stop located between the lenses. An angle of a field of view of the second lens group is less than 100 degrees. The reflecting lens has negative reflective power and has a curved reflecting surface to reflect the image light beam passed through the second lens group.

主权项

1. A projection lens for a projection device having a light valve, the light valve being adapted to provide an image light beam, the projection lens comprising:
a first lens group having positive refractive power; a second lens group having positive refractive power and disposed at a side of the first lens group far away from the light valve, the second lens group comprising a plurality of lenses, wherein the image light beam crosses an optical axis of the first lens group and then crosses an optical axis of the second lens group when the image light beam passes through the projection lens, and an angle of a field of view of the second lens group is less than 100 degrees; and a reflecting lens having negative reflective power and located at a side of the second lens group far away from the first lens group, the reflecting lens having a curved reflecting surface to reflect the image light beam passed through the second lens group.