Multi-display device and multi-display system

A multi-display system comprising:

• a multi-display device including a plurality of image projecting means for projecting partial images on a screen so as to construct one image as a whole, the partial images overlapping to have the edges thereof superposed on edges of adjoining partial images in shared fields on the screen, and a light level adjusting means for adjusting an amount of light to be projected on each shared field so that the luminance level in the shared field will agree with the luminance levels in the other fields except the shared fields, and for displacing a light level adjustment range within which an amount of light representing one edge of each partial image to be projected is adjusted relative to an amount of light representing the other edge thereof;
• an imaging means for picking up an image displayed on the screen of said multi-display device;
• a luminance detecting means for sampling a luminance signal from an image signal produced by said imaging means so as to detect the sizes of the shared fields and the luminance levels in the shared fields;
• a magnitude-of-displacement calculating means for calculating a magnitude of displacement, by which said light level adjusting means should displace the light level adjustment range, according to an output of said luminance detecting means;
• and
• a control means for extending control so that said light level adjusting means will displace the light level adjustment range by the magnitude of displacement calculated by said magnitude-of-displacement calculating means.

An adjusting method for a multi-display device comprising a plurality of image projecting means for projecting partial images on a screen so as to construct one image as a whole, the partial images overlapping to have the edges thereof superposed on edges of adjoining partial images in shared fields on the screen, and a light level adjusting means for adjusting an amount of light to be projected on each shared field so that the luminance level in the shared field will agree with the luminance levels in the other fields except the shared fields, and for displacing a light level adjustment range within which an amount of light representing one edge of each partial image is adjusted relative to an amount of light representing the other edge thereof, said adjusting method comprising the steps of:

• picking up an image displayed on the screen of said multi-display device and outputting an image signal;
• sampling a luminance signal from the image signal so as to detect the sizes of the shared fields and the luminance levels in the shared fields;
• calculating a magnitude of displacement, by which said light level adjusting means included in said multi-display device should displace the light level adjustment range according to detected information of the sizes of the shared fields and the luminance levels in the shared fields;
• and
• extending control so that said light level adjusting means will displace the light level adjustment range by the magnitude of displacement.