Thermochromic ink is mixed with concrete. Nickel chromium wires, which heat up when electric current is passed through them, are set beneath the concrete surface. The area above the wire changes colour when a certain temperature is reached. The arrangement of these wires beneath the concrete allows the display of graphics and information.
http://www.innovation.rca.ac.uk/archive/pr_sing.php?i=1
http://www.innovation.rca.ac.uk/archive/pr_sing.php?i=1
http://www.innovation.rca.ac.uk/archive/pr_sing.php?i=1
My so called life* 
January 5, 2005 at 7:56 pm
Looks like it only works when you use infrared goggles or something like that, making temperatues visible… why else are the pictures so very blue???
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January 6, 2005 at 1:26 am
Look at the pdf. There you have full colored pics. It would not be useful if you needed googles.
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