This video can be found on youtube.
Check out the other one, and some other of my videos
This is merely an instructable to explain how this device operates. I hope everything is not too obfuscated.
This prototype consists of three 8x8” modules. Each module operates independently of each other. Each module consists of 4 “pixels”. Each pixel is 4 inches square and consists of 21 LEDs, two IR emitting diodes, and two IR photodiodes. The mode of sensing is active infrared.
Check out my Color Changing Glowing Faucet
The IR sensor is a simple voltage divider former by two parallel IR photodiodes which are wired reversed biased. When a photodiode is reversed biased (like an LED connected up backwards) it acts like a variable resistor which changes resistance with respect to the amount of light (mainly infrared light) falling on it. The high resistance of the second static value 1 Megohm (R2) provides a voltage divider with the dividing node rising in voltage with an increase in IR light falling onto the photodiodes(R1).