Afocal video-pixel lens for tricolor LEDs

An afocal system keeps parallel any two parallel rays emitted by a pair of point sources. If they have the same intensity at identical angles, this design will ensure that the far-field intensity will be higher than that of the bare sources as well as giving same the intensity to both, so that color balance is preserved. If these sources are of different color, it is possible to mix them in the far field while increasing the intensity in a prescribed way. If a third LED is placed at the midpoint between the other two, its intensity pattern will still be close to the one created for the other two souces. This enables the pixel to color-mix red, green and blue LEDs while increasing their apparent intensity and preserving the color-balance of the video signal across the far field. This enables large active-video screens to redirect and intensify their light towards the audience, instead of just spreading it out uselessly.