prism assemblies for projector display systems disclosed receive inputs from discrete color channels ( e . g ., red , green and blue channels . in one embodiment , “ off state ” light from the red , green , and blue dlp modulation may be reflected away from on - state light paths within the prism , tending to avoid uncontrolled scatter . in other embodiments , by keeping the colors separate for much of the prism path length , power levels may be significantly reduced at typical failure points . light efficiency may be increased significantly when using discrete light sources like leds and lasers by removal of the additional red , green , and blue separation and re - combination losses .