Human Theremin using Infrared Light
The guys over at Nerd Kits have made a cool Human Theremin project that uses Infrared Light. IR light from an infrared LED is bounced off someones hand and some of the light is reflected back onto an infrared transistor. The closer the hands are the more IR light is reflected back onto the IR transistor. The output of the IR circuit is fed into a Nerd Kit microcontroller and
