Patent ID: 6702446
Filing Date: 2004-03-09
Classification: H04N

Abstract:
A projection display device comprisingan illumination system having a light source and an optical guiding mean for providing an illumination beam, color filter means provided on a wheel, for transmitting colored portions of the illumination beam for illuminating the display panel, and an image display system having a display panel for modulating the colored portions of the illumination beam with image information an projecting an image on a screen, the color filter means comprising adjacent spiral-shaped filter portions for simultaneously illuminating portions of the display panel by the colored portions of the illumination beam so that the portions of the display panel are consecutively illuminated by the colored portions of the illumination beam, the spiral-shaped portions extending from a first radius to a second radius of the wheel, the second radius being larger than the first radius, and the first and second radii depend on the size of the display panel, characterized in that a maximum cross-section in a radial direction of a spiral-shaped portion of a color selected from the group of red, green, blue and white extends from the first radius to the second radius, so that during the instant when the maximum cross-section in the radial direction is present in the illumination beam, the display panel is substantially entirely illuminated by the selected color.