[youtube= [Kyri] has made a simple circuit to do color detection using an RGB LED. Simply set the LED to the color you want to detect then wave the object over it. Another LED will light up if the … ...

An attempt at using a light frequency sensor didn’t work either. What did finally work, was a luminosity sensor shown above. Finally, his prototype worked.

Researchers tested individual color detection using a Mario image. Here, they're testing out the red light detecting system. A green Mario shows the green system working.