An apparatus and method of a lamp including an optically transmitting, thermally conductive substrate is provided. The substrate has a first side, a second side, and at least one edge. At least one solid state light source, such as but not limited to a light emitting diode, is disposed on the first side of the substrate. The at least one solid state light source (e.g., light emitting diode) includes at least one junction having a first junction temperature. The substrate used is an optically transmitting, thermally conductive substrate, with a thermal conductivity greater than or equal to about 3 W/mK.
STATEMENT OF GOVERNMENT INTEREST
 This invention was made with U.S. Government support under DOE Cooperative Agreement No. DE-EE0000611, awarded by the U.S. Department of Energy. The U.S. Government may have certain rights in this invention.