Adafruit rgb colour sensor with ir filter arduino compatible adafruit 1334 p the adafruit rgb colour sensor uses the tcs34725 sensor which includes 4 x photodiodes covered by an ir blocking filter for greater accuracy three of the photodiodes are covered with coloured filters to provide the individual rgb values and the fourth is left clear for an overall value with a dynamic range of 3 8 million to 1 and adjustable integration time and gain it s even possible to use this sensor behind dar