Conclusion
There are different possibilities to predict the LED’s
lifetime. Beside TM-21, other methods and mathematical
functions have been tested. The Arrhenius behavior could be
observed in several examples. For a correct extrapolation a
fitting function should represent the measurement data in the
best possible way. There are suggested functions whose
parameters correspond with the Arrhenius plot. In further
investigations steps of aging should be observed and predicted
for the curves of lower temperatures