Patent ID: 8810478

Claim:
A multi-screen display device comprising a plurality of image display devices, wherein said plurality of image display devices include one master device and one or a plurality of slave devices communicable with said master device, each of said image display devices comprising: a light source; a light valve that modulates light of said light source; a screen onto which an image is projected by modulated output light of said light valve; and a luminance sensor that detects luminance of light from said light valve and outputs a luminance detection value in a case of said light valve being in an off-state, wherein said master device includes a setting part that sets a luminance setting value unified among said plurality of image display devices based on a value in accordance with said luminance detection values in said plurality of image display devices, wherein each of said image display devices further comprising: a controller that controls luminance/chromaticity of an image displayed on said screen in each device based on said luminance setting value; a storing part that stores said luminance detection value; a calculator that calculates a luminance change value as a value in accordance with said luminance detection value by use of said luminance detection value stored into said storing part and an initial luminance detection value stored into said storing part; a temperature sensor that detects a temperature in said luminance sensor; a corrector that corrects said luminance detection value by use of an output of said temperature sensor, and outputs a temperature-corrected luminance value; and an operator that computes an individual correction factor specific to each of said image display devices based on said target luminance value, wherein said setting part in said master device sets a target luminance change value as said luminance setting value with respect to a target luminance value unified among said plurality of image display devices, based on said luminance change values in said plurality of image display devices, said storing part stores said temperature-corrected luminance value and said individual correction factor, said calculator calculates a luminance change value by use of said temperature-corrected luminance value stored into said storing part and an initial temperature-corrected luminance value stored into said storing part, and said controller corrects said individual correction factor based on said target luminance change value, and controls luminance/chromaticity of an image displayed on said screen in each device based on said corrected individual correction factor.