What is randomized common ends?

When some light guides are bundled together in a single common end this becomes a physical impossibility to get the same level of light in each light guide since the lamp emission is not completely even on the screen plane. To minimize the differences individual fibers are "randomized" or mixed so that each light guide gathers its light from various geometrical points inside the screen. Light issuing by individual ends in a randomized system is considerably more even but not completely so. In polymer fiber systems state of the art optical randomizers can get greater evenness with little loss.