In referring to LEDs, the United States Department of Energy (DOE) states that no other lighting technology offers so much potential to save energy and enhance the quality of our building environments. Thermal management is critical to LED performance because the lifetime is a function of junction temperature. Rudi Hechfellner, Applications Manager for Philips Lumileds Lighting, San Jose, California says that thermal management is by far the most critical aspect of LED system design. LED system manufacturers are addressing this challenge by seeking out improved heat sink designs, high efficiency circuit boards, high thermal conductivity enclosures and other advanced thermal design techniques.