news digest ♦ LEDs
Now that RGB LEDs have already conquered the market for pico projectors the next segment in their sights is that of office projectors. This has been made possible by the enormous brightness increase of green LEDs.
The prototype with a single chip achieves 410 lm and emits at a wavelength of 553 nm. Since a greater proportion of green than red or blue is needed in a projector to produce white light, the increase in the brightness of the green LED has a significant effect on the overall system brightness.
With these LED prototypes it is possible to produce systems that provide the system brightness of 2000 lm that is needed for office projectors. LED projectors will therefore be powerful enough for large diagonals of more than two meters. Such applications have only been possible with projectors that use conventional light sources such as high- intensity discharge lamps.
“Doubling the brightness of the green LED is a giant leap forward and removes the restriction that LEDs are suitable only for small projectors”, said Volker Mertens, Director Marketing Industry at OSRAM Opto Semiconductors.
Apart from providing brilliant image reproduction with saturated colors, LEDs enable projectors to be virtually maintenance-free because they have a life of 30,000 hours. By contrast, high-intensity discharge lamps need to be replaced after only about 400 hours. Projectors with LEDs also respond more quickly to on/off switching, and they support stepless dimming. They can therefore adapt very easily to ambient light conditions and reduce energy consumption. The color space can be set with a high degree of flexibility thanks to electronic control of the individual colors.
Thanks to new high-brightness green LEDs, the LED projectors of the future will be able to produce images with diagonals of several meters. The projected images themselves will appear brighter for the same lumen value than those produced by conventional light sources thanks to the saturated colors of the LEDs used.
Osram is part of the Industry sector of Siemens and one of the two leading lighting manufacturers in the world. Its subsidiary, Osram Opto Semiconductors GmbH in Regensburg (Germany), offers its
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customers solutions based on semiconductor technology for lighting, sensor and visualization applications.
Aixtron Receives Multiple Order from Huga Optotech
AIxtron will supply a double-digit number of AIX G5 HT 14x4-inch systems to manufacture GaN ultra- high brightness LEDs.
Aixtron has a repeat order for multiple MOCVD reactors from existing customer Huga Optotech.
The order comprises a double-digit number of AIX G5 HT 14x4-inch configuration deposition systems. Huga Optotech placed the order in the course of 2010 and after delivery of the systems between the fourth quarter of 2010 and the first quarter of 2011, they will be used for the production of GaN- based materials for ultra-high brightness (UHB) blue LEDs. The local Aixtron support team Taiwan will commission the new reactors in Huga’s newly expanded Taichung facility.
“Huga Optotech has been particularly impressed with the overall performance of our first Aixtron G5 HT MOCVD system”, C.N. Huang, Huga Optotech President comments. “Factors that have influenced our decision centre on the excellent performance we have seen from the G5 Planetary system, plus its capability to perform continuous runs without baking or cleaning. This has been achieved as smoothly and efficiently as we could wish. These and other positive factors have reassured Huga Optotech management and engineers alike that they can have the highest confidence with the AIX G5 HT platforms on order. We plan to base our complete current expansion around the G5.”
Huga Optoech is one of the major manufacturers of high-brightness GaN LED wafers and chips in Taiwan. Established in May 1998, it first achieved mass-production of its own blue LED chip product in 2001. Today it is committed not only to the manufacture and further development of GaN LED chips, but also other GaN components such as laser diodes, UV emitters and GaAs-based devices for communications, etc.
The G5 HT is Aixtron´s flagship MOCVD system
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