Patent attributes
The rear projection lens device comprises a fixed lens barrel, a first lens barrel having a front lens group, a second lens barrel having a rear lens group, and a rotation stopper. The first lens barrel is helicoid-coupled with the fixed lens barrel, and moves in an optical axial direction by rotating relative to the fixed lens barrel. The second lens barrel is helicoid-coupled with the first lens barrel and moves in the optical axial direction so as to change an interval between the front lens group and the rear lens group when the first lens barrel rotates. The rotation stopper allows the second lens barrel to move in the optical axial direction, but stops the rotation around the optical axis. A zoom adjustment and aberration correction associated with the zoom adjustment are conducted concurrently only by rotating the first lens barrel.
