Lens compatible with multi-size LCD display screens

The utility model discloses a multi-piece large-size LCD projection lens. The multi-piece large-size LCD projection lens comprises a Fresnel lens, a first lens, a second lens, a doublet lens, a diaphragm, a third lens and a fourth lens which are sequentially arranged from an LCD end to a screen end, the fourth lens is a positive meniscus lens, the third lens is an eight-order aspheric lens, the second lens is a biconvex lens, and the first lens is an eight-order aspheric negative lens; according to the utility model, the brightness of the LCD projector is improved by increasing the size of the light source window, increasing the clear aperture of the lens, reducing the relative aperture of the lens, plating the antireflection film on the surface of the lens and the like; the LCD resolution is improved by increasing the number of lenses of the projection lens, adding aspheric lenses, adopting a balsaming lens and the like. 本实用新型公开了一种多片式大尺寸LCD投影镜头，包括由LCD端至屏幕端依次设置的菲涅尔镜片、第一镜片、第二镜片、双胶合透镜、光阑、第三镜片以及第四镜片；所述第四镜片为正弯月形透