Due to the small source size, long lifetime and high luminous efficacy, light emitting diode (LED) light sources are becoming increasingly popular in numerous fields. The short response time, high intensity and homogeneity of the emitted light make the LED sources indispensable in machine vision system. In such systems, the quality and reliability of the light sources is of utmost importance. In this thesis, we have developed a system for accelerated ageing of LED modules by thermal and current stress. The main goal of the accelerated aging is to rapidly assess the quality of LED modules and identify assembly errors that might lead to premature failure of the module and thereby of the light source. The system for accelerated ageing is designed to operate 32 LED modules and provides 128 digitally controlled current sources. The system is continuously monitoring the voltage and temperature of the tested LED modules and instantly reports any detected failures or deviations from normal operation. The accelerated aging process can be fully managed from a user friendly interface.
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