Lumen Maintenence Overview

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Transcript of Lumen Maintenence Overview

  • 1. XLamp XR-E Lighting-Class LEDLumen Maintenance July 2009

2. Semiconductor Reliability Testing

  • Reliability test methods and acceptance criteria for semiconductor components have been standardized (JEDEC, EIAJ, others) and practiced for decades
    • Think:processors, regulators, microcontrollers, etc..

3. LED Reliability Testing

  • LEDs are semiconductorcomponents that happen to emit light
  • Cree conducts all the traditional standardized semiconductor component reliability testing on all of our LED lamps( )
  • Cree has been active in leading the industry standardization of an additional test series IES LM-80-2008 to characterize the Lumen Maintenance aspect of LED semiconductor components

4. Lumen Maintenance Definition L 70= 10,000 hours

  • Definition: change in light output of a light source over operational life, relative to initially measured light output
  • L xx= time to xx% of original light output
  • L 70= time to 70% of original light output
  • L 50= time to 50% of original light output

Lumen Maintenance:400W metal halide lamp Traditional light sources gradually dim then fail catastrophically (burn out) 5. LED Lumen Maintenance History