Fresnel lens is used in projection system, its function is to collimate light and focus light.

The Fresnel lens used in the projector is to improve the resolution, clarity, and brightness of the projector screen. The thread pitch and tooth profile are rationalized, and the keystone correction range is increased to raise the picture. The lens condenser objective is eccentric, so that the projector can achieve a good viewing effect whether it is suspended or placed on a desktop.