a. a first light source and a second light source, the first and second light sources being operatively configured to provide amounts of light independently controllable during operation; and

b. an optical system having an input aperture system and an output aperture system, the output aperture system displaced by a predetermined distance along a forward direction from the input aperture system, the optical system operatively coupled with the first and second light sources and configured to direct light received simultaneously at the input aperture system from the first and second light sources to the output aperture system, the output aperture system configured to output the light from the first light source into a first output light distribution and to output the light from the second light source into a second output light distribution at least in part different from the first output light distributions,

wherein the optical system comprises a light guide extending along the forward direction and configured to guide the light received at the input aperture system along the forward direction by total internal reflection of the light at surfaces of the light guide, wherein for a cross-section through the light guide in a first plane parallel to the forward direction, the light guide has opposing sides that are linear and define a tapered thickness along the forward direction and, for a cross-section through a second plane perpendicular to the forward direction and perpendicular to the first plane, the light guide has a curved shape.