Method and apparatus for use in a projection display to prevent ghost images on or near a projected image

Abstract

A method for use in a projection display to prevent ghost images on or near a projected image, wherein the projection display comprises an illumination system and an imaging system, the illumination system including a light source; an illumination module; a field lens; and a reflection device. The imaging system includes the field lens; an imaging module including a stop; and a screen. The method comprises changing the surface profile of the surface zone, which would otherwise involves generation of a ghost image, of the surface S1 of the field lens so that the ghost image is reflected to the area outside of the stop or is scattered and the effect of reducing or preventing ghost images can thereby be achieved.

Dependencies are inferred from the claim text.