Patent ID: 8480236

Claim:
A projector comprising: an illumination system which has a light source, and a light control unit opened and closed to shield a part of light emitted from the light source; a light modulation device illuminated by illumination light received from the illumination system; an air supply device which supplies air to the light control unit and the light modulation device, wherein the air supply device has a first air supply device for supplying air to the light control unit, and a second air supply device for supplying air to the light modulation device, an air supply control unit which decreases an air supply amount to the light modulation device when increasing an air supply amount to the light control unit in accordance with a relatively closed condition of the light control unit, wherein: the air supply control unit controls the air supply amount to the light control unit and the air supply amount to the light modulation device by adjusting voltage applied to the first air supply device and voltage applied to the second air supply device, and the air supply control unit maintains a substantially constant total power consumption by the first air supply device and the second air supply device by: increasing a first power consumption of the first air supply device and, at the same time, decreasing a second power consumption of the second air supply device by the same amount by which the first power consumption is increased, and decreasing the first power consumption of the first air supply device and, at the same time, increasing the second power consumption of the second air supply device by the same amount by which the first power consumption is decreased.