Patent ID: 8106894

Claim:
A projector comprising: a housing; a light source installed in the housing; a color wheel for separating the light from the light source into color light; an image modulator for modulating the color light from the color wheel, and projecting the color light to form an image on a screen; a scalar connected to the image modulator for controlling the image modulator to create a gray-level image, wherein the gray-level image includes gray levels, for facilitating adjustment of a color wheel delay of the projector, wherein the adjustment includes minimizing one of yellow and purple color in the projected gray-level image for producing a gray image with substantial absence of color; and a control circuit for projecting an on screen display (OSD) on a screen, the OSD comprising the gray-level image created by the scalar, and a user interface for manually adjusting the color wheel delay of the projector to produce a gray image on the OSD with substantial absence of color, thereby synchronizing the color wheel with the image modulator to achieve said adjusted gray image having substantial absence of color.