An optical system, projector and method are provided that include a projection gate between a light source array and a projection lens. The projection lens projects an image of the projection gate. A relay lens group between the light source array and the projection gate prevents the projection lens from projecting an image of the light source array. A lamp housing is provided for use with a projector housing. The lamp housing includes a light source array and a relay lens group located between the light source array and a projection gate in the projector housing. An illumination source for optical fibers is provided that includes a relay lens group between a light source and a coupling in a housing. The relay lens group prevents an image of the light source from being formed at input ends of optical fibers positioned in the coupling.