High-brightness Green LEDs

OSRAM OptoSemiconductors have developed a pre-production green LED based on the OSTARplatform that is twice as bright as its predecessors and has a luminous surfacethat is uniform. The single-chip LED benefits from a green phosphor converter.Initial samples are available, and OSRAM is currentlyworking with partners to develop appropriate LED data projectors such as thoseused in the office and education markets. OSRAM Opto Semiconductors expects the LED to be widely available to projectormanufacturers in the summer of 2011.

The prototype with a single chip achieves 410 lm and emits at awavelength of 553 nm. Since a greater proportion of green than red or blue isneeded in a projector to produce white light, the increase in the brightness ofthe green LED has a significant effecton the overall system brightness. With these new LED prototypes, it is possibleto produce systems that deliver an overall brightness of 2,000 lm which isrequired for office and education applications. LED projectors will soon bepowerful enough for screen sizes of more than two meters diagonal. Until now, suchapplications have only been possible with projectors that use conventionallight sources such as high-intensity discharge lamps.

High-brightness Green LEDs