Projection display device

摘要

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 colors disposed near the light sources in the respective colors for detecting light leakages from the light sources in the respective colors, a cooling unit 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 a cooling controller for controlling the cooling unit for the light sources in the respective colors.

主权项

1. A projection display device having a plurality of light sources and displaying images based on a video signal, comprising:
a plurality of temperature sensors, light sensors, and cooling means installed in association with the light sources, respectively; an amount-of-light controller for controlling amounts of lights emitted from said light sources depending on corresponding output signals from said light sensors; a cooling controller for controlling cooling operation of said cooling means depending on corresponding output signals from said temperature sensors; and a central processing unit (CPU) for controlling said amount-of-light controller depending on an output signal from a temperature detecting means installed in a housing to keep constant a ratio of the amounts of lights emitted from said light sources, wherein said plurality of light source are controlled by Pulse Width Modulation (PWM), and PWM switching frequency is different from a frame frequency of said video signal.