Rear projection lens

The utility model relates to a rear projection lens, comprising a cylinder body and a fixing base. The cylinder body is provided with a first screw and plural adjusting portions. The fixing base is provided with a second screw and at least one opening. The cylinder body is sheathed by the fixing base and the first screw is bonded with the second screw. The opening is arranged oppositely the adjusting portion. When one of the adjusting portions passes through the opening, the cylinder body and the fixing base move relatively an axial distance. The adjusting portion of the rear projection lens of the utility model passes through across the opening to make the cylinder body and the fixing base turn oppositely and move upward a distance on the axis, so a focusing adjusting can be directly processed on the machine by using a rod-shaped thing or a finger without detaching the lens. The risk of damaging the dear lens is reduced and the good rate of the product is improved. In addition, the relative position of the cylinder body and the fixing base of the utility model can be fixed after the focusing adjusting to ensure the stability of the product quality.