OSRAM Opto Semiconductors' MultiLED black surface LEDs (LRTB GFTG) were used in the led display wall in Tian An Men Square in Beijing. Instrument Systems GmbH introduces its new calibration LEDs to its ACS-530 Series.The special feature of the new products is their temperature-stabilized high-powerLED, according to the company. The new calibration LEDs enable customers to check their instruments easily and reliably. It also means that the photometric value canbe recalibrated by customers in conformity with the CIE International Commission onIllumination. Before testing is carried out, the LEDs are calibrated using strictlytraceable standards for luminous flux and luminous intensity in the Instrument Systems test lab.
The calibration LEDs have a reproducible and stable optical output power that is essential for reliable measurements. They also feature a particularly high photometric stability of 0.1%. The high-power LED is housed in a casing with exceptionally low thermal conductivity together with a TEC element and a temperature sensor inorder to achieve this high stability. The high-power LED is also cooled with the assistance of the TEC element. This eliminates sensitivity to external temperature fluctuations and demonstrates significantly reduced degradation behavior by comparison with heated standard LEDs.
The calibration LEDs from Instrument Systems are supplied in the three basic colors red, green, blue, as well as in white. Over and beyond the photometric parameters luminous intensity and luminous flux, they can also be used for checking resultsfor dominant wavelength, color coordinates and color temperature. A temperature control unit and a constant current source are necessary for operation of the calibration LEDs. They are controlled using the LED Control software developed by Instrument Systems. A PID parameter set optimized for each standard guarantees fast stabilzation and means that the entire measuring system can be deployed immediately.
They were selected for the uniform display results and high color fidelity across the entire viewing angle. The black surface of the LED offers very good contrast both at night and in the day time, and from a distance.
The MultiLED allows displays on the 2.9m x 4.5m wall, installed for China¡'s 60th National Day celebrations, to be seen by viewers from a distance of up to 150m. The black surface of the LED on the display provides excellent contrast and impressive depth of color. This visual sharpness is important to video displays, particularly in broad daylight and playing high resolution videos. In addition, very high uniformity and brightness is achieved by using the latest high-power Thinfilm and ThinGaN technology, enabling the display colors remain constant from all viewing angles.
¡°OSRAM¡'s LEDs are among the best LEDs on the market,¡± said Zhang Guang Qing, Chairman of the Board of Toecstar, the company which built the display wall. ¡°Their MultiLED products enable very high uniformity in terms of color and brightness. What¡'s more, they are also very reliable. This is very important as maintenance costs can be brought down.
The MultiLED family comes in a 6-lead package that delivers improved thermal management and increased reliability, making it the ideal choice for long term installations such as display walls.
According to DisplaySearch, LED revenues for outdoor displays will grow 50% from 2009 to 2012. The fastest growing markets are in China and Asia Pacific. They are expected to overtake North America and Europe/MiddleEast by 2011. Since the Olympics last year, LED display have gained momentum in China. With the Expo in Shanghai coming up next year, the market is set to experience tremendous growth, achieving a CAGR of 15.1% since 2007.
High-power MultiLEDs offering high contract and complete color fidelity to display wall installed for China¡'s 60th National Day.
