Light-emitting diodes for space applications

The use of Light Emitting Diode (LED) devices for illumination inside space cabin and outside have been well exploited in the past few years; these include, for example, the in-cabin application on the bio-science satellite in 2007 and the out-of cabin application on spacecraft in 2008 to shine on the first step in space of Chinese astronaut. The simulation of the optical properties has been performed to optimize the brightness of the LED lamp. The thermal property of assembled LED lamp has been experimentally characterized and used in combination with the numerical simulation to improve the precision of determining the active layer temperature of the LEDs packed in the lamp. The measurement precision of the LED active layer temperature is improved to a value better than 1 K.