A lamp having a front surface from which light is emitted and that includes a high efficiency light source assembly producing a beam having a 3 dB beamwidth of greater than 100°, and which includes a substrate, a high efficiency light source supported by the substrate;and a dome-lens that contains the high efficiency light source. Also, an optical assembly is positioned to receive light from the light emitting diode assembly and to produce a headlamp light beam emitted from the front surface of the lamp. Further, an annular light block defines an annulus and is placed about the lens, so that the lens protrudes through the annulus, thereby creating a sharp boundary for the output light beam.