Compact, telecentric projection lenses for use with pixelized panels

摘要

Telecentric projection lenses for use with pixelized panels (PP) are provided. The projection lenses have a negative first unit (U1) which has at least one negative meniscus element (N1) having at least one aspheric surface and a positive second unit (U2) which has at least one positive element (P1) having at least one aspheric surface. The lens' aperture stop (AS) is located between the two units, and a third lens unit (U3) may be used in the vicinity of the aperture stop to improve the correction of axial color. The lenses have small forward vertex distances, small clear apertures, and long back focal lengths which make them particularly well-suited for use in the manufacture of compact projection systems.