OSRAM Opto Semiconductors has developed the smallest RGB Multi ChipLED especially for high-resolution full-color video screens with large diagonals and small viewing distances. The tiny dimensions of these components enable a very large number of pixels to be accommodated in a small display area. The LED is housed in a black package that reflects hardly any ambient light at all. The LED emits light in brilliant colors with excellent contrast.
Thanks to the Multi ChipLED, high-resolution full-color video screens, for example in television studios, modern conference rooms, concert halls and trade fairs, offer brilliant colors and high contrast from all viewing angles. Press picture: OSRAM
OSRAM's latest RGB product in a miniature package takes up an area of only 1.6 mm x 1.6 mm and measures just 0.9 mm high. With this LED it is possible to have a pixel spacing of only 2 mm so that a great many pixels can be provided in a small area. For example, an area of less than 10 m² is sufficient to display pictures in HDTV quality and accommodate more than 2 million pixels. A 2.5 x 4.0 m display achieves a system luminance of 1500-2500 cd/m². This corresponds to around ten times the luminance of a conventional LCD TFT screen.
Perfect color mixing takes place in the package itself thanks to the specially developed encapsulation material. Color appearance remains constant across the entire viewing angle, and the picture appears vibrant even when viewed from the side. Ambient light cannot ruin the picture quality because it is barely reflected at all by the black package in which the LED is housed.
Inside the Multi ChipLED there is a red chip and a blue and a green chip in Thinfilm and ThinGaN technology. If the RGB-LED is operated with a current of 20 mA the individual chips produce typical luminous intensities of 250 mcd (red), 350 mcd (green) and 70 mcd (blue). The typical efficiency of this luminous intensity is 4 cd/W, which corresponds to a luminous efficacy of 12 lm/W. The beam angle of the LED is +- 60°.