Patent ID: 7490966

Claim:
An illumination system, comprising: a light source suitable for providing a light beam; a light integration rod disposed in a transmission path of the light beam, the light integration rod having a light input end and a light output end opposite the light input end, and the light input end of the light integration rod having two indentations, the two indentations forming an airflow channel, the light integration rod comprising: a pair of opposing panels including a first panel and a second panel; and another pair of opposing panels including a third panel and a fourth panel, wherein the third panel and the fourth panel are connected between the first panel and the second panel, and the first panel and the second panel retreat inward at the light input end of the light integration rod between the third panel and the fourth panel to form the indentations; and a color wheel disposed between the light source and the light integration rod in the transmission path of the light beam, the light input end of the light integration rod being adjacent to the color wheel.