| 摘要 |
<p>A projection display device includes light sources having light-emitting elements for emitting lights in R, G, B colors, temperature sensors for the respective colors disposed near the light sources in the respective colors, light sensors for the respective colorsdisposcd near the light sources in the respective colors for detecting light leakages from the light sources in the respective colors, cooling means for cooling the light sources in the respective colors, light modulators employing three panels of liquid crystal devices, a projection optical system, an amount-of-light controller for maintaining a predetermined ratio of the amounts of lights emitted from the light sources in the respective colors, and cooling controller 7 for controlling the cooling means for the light sources in the respective colors. The light sensors for the respective colors measure the respective amounts of lights emitted from the light-emitting elements, and the amount-of-light controller compares and adjusts the amounts of lights in the red, green, and blue colors emitted from the light-emitting elements to thereby keep a white balance. It is possible to maintain displayed images with an optimum white balance even if the junction temperatures of the light-emitting elements vary to change the light emission efficiency and even if the light-emitting elements are deteriorated from long-term use, thus reducing the amounts of lights emitted thereby.</p> |
