Method of illuminating a light valve with improved light throughput and color balance correction

The invention relates to methods for illuminating light valves such as those used in color video displays and in particular relates to methods of illuminating such light valves with improved throughput and adjustable color balance. A method of illuminating a light valve using a light source with modulated intensity to improve light throughput and color balance while minimizing loss of color resolution. A light valve is provided that includes a light input, a light output and a spatial light modulator including an array of pixels. The spatial light modulator is illuminated through the light input with light generated by a light source having a nominal lamp power dissipation level. Image data is provided and the array of pixels is configured based on the image data during a display period so that the image data is represented in light from the light source received at the light output. During a portion of the display period, the intensity of the light generated by the light source is increased to a high level above the nominal lamp power dissipation. During another portion of the display period, the intensity of the light generated by the light source is decreased to a low level below the nominal lamp power dissipation level. The average lamp power dissipation level over the display period is maintained at a level that does not exceed the nominal lamp power dissipation level. The light valve provided may additionally include a color sequencer for sequentially selecting one of a first, a second, and a third colorband of light that may reach the light output. Alternatively, the light valve provided may include a first, a second, and a third spatial light modulator and a color separator for directing a first, a second, and a third colorband of light from light received at the light input to the first, the second, and the third spatial light modulator, respectively. The light valve provided may also include a first, second, and third shutter between the color separator and the first, second, and third spatial light modulator, respectively.