Abstract: A light emitting panel assembly is provided. The light emitting panel assembly includes: a housing; a light guide within the housing, the light guide having a first major surface with a plurality of extraction elements, a second major surface, a lower surface, an upper surface, a light source adjacent to the lower surface of the light guide; and an upper guide reflector having a diffuse reflective surface adjacent to and facing the upper surface of the light guide, whereby light from the light source traveling through the light guide toward the upper guide reflector spreads within the light guide, and whereby the upper guide reflector homogenizes the light before the light is redirected to the light guide. A luminaire comprising such a light emitting panel assembly is also provided.