Robust multichip LED for high-contrast displays in outdoor applications

Large-format outdoor displays, for example at rock concerts, at sporting events or for perimeter advertising, are the most important target applications for the new Displix black and Displix blackprint multichip LEDs from Osram Opto Semiconductors. These robust high-contrast high-power LEDs can withstand high humidity levels, wide fluctuations in temperature and even torrential rain.

The high-quality multichip LED is available as Displix black in a black package with a black reflector and as Displix blackprint in a white package with black overprinting and white reflector. Displix black offers  excellent contrast even in direct sunlight and offers precise color rendering even after a long operating time. Their brightness values are also impressive. The typical light intensity at the Illuminant D65 white point (at a color temperature of 6504 Kelvin), is 1450 millicandela (mcd) at an operating current of 20 milliamps, which appears very bright in the black package. Under the same operating conditions Displix blackprint is even more intense at 2950 mcd with good contrast.

The 4.5 x 4.5 x 2.1 mm package for both Displix versions contains three chips with typical wavelengths of 625 nm (red), 528 nm (green) and 470 nm (blue). This means that individual LEDs do not have to be combined into an RGB cluster. This reduces the pixel spacing and improves the resolution for the same area. Sven Weber, Marketing Manager for LED Displays at Osram Opto Semiconductors, said: “People are more and more used to seeing HD images in their homes and on HD compatible devices so the requirements placed on outdoor displays are changing. The two new Displix versions enable long-life displays with high resolution, high intensity and excellent contrast to be produced for a wide variety of applications.”

Thanks to SMT technology the LEDs can be processed at reduced cost. With a height of 2.1 mm there is enough space for further standard processes such as silicon encapsulation for added protection against harsh outdoor conditions. Special shading elements can also be easily fitted. Both measures extend the life of the LED, which may be more than 100,000 hours depending on the ambient temperature. At the same time they provide the basis for long-term stability. This is evidenced by the approval of the components for various harsh ambient conditions such as specialty corrosive gases, aging in direct sunlight and resistance to heavy rain.

The Displix LEDs can be seen for the first time at electronica 2012 (November 13 to 16 in Munich) on Booth 107 in Hall A3.