Cyan, magenta and yellow filters transmit two primary colours. Any other colour present in the light is absorbed. A cyan filter transmits blue light and green light. It absorbs red light.

Modern color theory (and what's used in printing and elsewhere that requires subtractive color), shows that magenta, yellow and cyan are the best colors to use in a subtractive color setup.

Why Nokia’s Lumia phones are cyan, magenta, and black (and perhaps yellow and white) According to designer Tiina Aarras, Nokia’s N9, Lumia 800 and Lumia 900 derive their distinctive shades of ...