Off-axis system for lcd projectors

Abstract

An off-axis system for LCD projectors comprises an LED light source, a condenser cup, a rear Fresnel lens, a heat insulation lens, an LCD, a front Fresnel lens, and a projection lens group, provided in sequence from light source to projection screen. The optical axis of the projection lens is inclined upward by 9.5 degrees, the front Fresnel lens is inclined by 3 to 6 degrees, and the LCD projector's base plane is inclined by 9.5 degrees. The invention solves image separation and optical loss by applying to all single-panel LCD projectors. The viewing wall and front lens form a 70-to-75.5-degree angle for keystone correction, and the LED light, condenser cup, rear Fresnel lens, front Fresnel lens and LCD form a 7-to-10-degree angle with the horizontal plane, and the reflection mirror and projection lens group form a 90-degree angle, achieving concentric alignment of optical axis to solve optical loss.

Dependencies are inferred from the claim text.