Applications for advanced solid-state lamps

Since lighting accounts for a large fraction of electrical usage in the industrial sector, the energy efficiency of lamp systems is of major interest. One promising technology which has the potential for use in specialised energy-efficieny lighting applications is solid-state lamp technology. There are many reasons solid-state lamps may be especially useful for new applications. They exhibit long lifetimes, in the order of 100000 hours. Coupled with the ruggedness inherent in solid-state devices, this indicates usefulness for low maintenance applications. Fast response times also make them ideal for some applications. This review surveys the state-of-the-art in solid-state semiconductor lamp technology, with a focus on the potential for such applications, and on energy efficiency and brightness considerations. The different types of solid state light source are described: LED, diode lasers, superluminescent diodes and electroluminescent diodes. Their operating characteristics are discussed and the following applications described: illuminated signs, exit-signs, traffic control lights, airport runway lighting, vision sensors illumination, spotlighting, interactive and fast adaptive lighting and fibre-optic channeled lighting.