System Level Reliability for Solid State Lighting Applications

Solid State Lighting (SSL) technologies and products are gradually pervading into our daily life. A SSL system is composed of a LED engine with a micro-electronics driver(s), integrated in a housing that also provides the optical, sensing and other functions. Knowledge of system level reliability is crucial for not only the business success of the future SSL applications, but also solving many associated scientific challenges. In practice, a malfunction of the system might be induced by the failure and/or degradation of the subsystems/interfaces. Extra costs, in terms of additional efforts/designs/parts, have been considered in order to secure the guaranteed reliability performance of SSL system. Most of SSL system designs, which allow few failures of the subsystem/interface during the application period, can be achieved with significant cost reduction when the system level reliability is well understood by proper experimental and simulation techniques. This paper will cover the reliability of total SSL systems including the reliability theories and practices for all (sub-) components, such as LED engines, drivers and fixtures.