Ultra wide angle zoom lens in projection display system

摘要

An ultra wide angle zoom lens for a projection display system including a liquid crystal panel displaying an image; a second lens group having a positive refractive power, formed by combination of two or more lenses, and correcting chromatic and spherical aberrations of incident light from the liquid crystal panel; a total reflection mirror reflecting the incident light from the second lens group in a predetermined direction; and a first lens group having a negative refractive power, formed by combination of two or more lenses, and correcting distortion and astigmatism of the incident light from the total reflection mirror. Here, a projection lens is constructed so that a magnification of the projection lens is adjusted by movement of the second lens group along an optical axis, and the first lens group is moved forward and backward according to the adjusted magnification of the projection lens so that lens focusing can be adjusted.