Solid-state lighting: lamps, chips, and materials for tomorrow

The aim of this article is twofold. First, we give a brief historical and forward-looking overview of conventional and SSL lighting technologies. We focus on SSL technology based on inorganic light-emitting diodes (SSL-LEDs), rather than that based on organic light-emitting diodes (SSL-OLEDs), as SSL-LED technology is more advanced and more likely to be first to enter general illumination applications. Second, we describe some of the simplest but most important lamp, chip, and materials design choices that will need to be made. We especially focus on the constraints imposed on those design choices if SSL-LED technology is to fulfill its promise for general illumination.