LED Degradation

[Powen]

Have anyone the experiences of LED degradation application use ALTA? The LED degradation curve will decrease the lightness at first, then will increase a little at the end. Any suggestions of this degradation curve? Or I should use another software(Weibull++/DOE...) for this situation.:confused:

[JON_BK]

Based on the my experiencies LEDs degradation happens steadily over time. What kind of temperature levels you applied and did you carry out some measurment system analysis to make sure that measurement system is able to provide high quality measurement data? Measuring LEDs is not easy thing especially id you are building own meausrment environments as we did.

[David]

I know that we have customers who have used ALTA and the degradation folio to measure the degradation of LEDs. A simple example is also installed with the application. The example is located by default at ...\Program Files\ReliaSoft\ALTA7\Examples\Degradation.

A couple of articles associated LEDs can be found below:

http://www.weibull.com/hotwire/issue38/hottopics38.htm (An Accelerated Life Testing Model Involving Performance Degradation)
http://weibull.com/hotwire/issue65/hottopics65.htm (Degradation Analysis in Step-Stress Accelerated Testing)

I hope this helps.