One example system includes a light source that emits light. The system also includes a waveguide that guides the emitted light from a first side of the waveguide toward a second side of the waveguide opposite the first side. The waveguide has a third side extending between the first side and the second side. The system also includes a mirror that reflects the guided light toward the third side of the waveguide. At least a portion of the reflected light propagates out of the waveguide toward a scene. The system also includes a light detector, and a lens that focuses light from the scene toward the waveguide and the light detector.