Patent ID: 8107019
Filing Date: 2012-01-31
Classification: G02F,G03B,G09G

Abstract:
1. A projection type image display device comprising: a lamp as a light source; a diaphragm for adjusting an amount of light irradiated from the lamp; a display device for generating image light by spatially modulating light that passed though the diaphragm: a projection lens for magnifying and projecting light outputted from the display device; a lamp driving portion for controlling power of the lamp; a cooling fan for cooling the lamp; a temperature sensor for detecting an ambient temperature of the lamp; a video signal input terminal to which a video signal is inputted; a diaphragm control angle calculating portion for calculating an angle at which the diaphragm is controlled according to a level of an input video signal inputted from the video signal input terminal, and outputting the angle as control angle information; a diaphragm driving portion for controlling the angle of the diaphragm according to the control angle information; a fan control signal generating portion for controlling rotation speed of the cooling fan according to a combination of the control angle information and the temperature detected by the temperature sensor; and a display device driving portion for converting the input video signal into a signal that allows the display device to display.