need/requirement under LM
How LM-79 testing can help assess LED luminary quality and performance?
We all believe in buying quality products. Discovery of LED is boon to our world. LED has replaced all the traditional lightning systems because of its quality, life and performance. Manufacturers are switching from manufacturing traditional lightning to produce LED lighting. Many of the manufacturers are making unsubstantial claims regarding colour quality, luminous flux (lm), efficacy (lm/w) and general quality. This can Lead to LED degradation. To ensure quality, a series of test has to be performed on LED luminaries for its long term survival. This is served by LM 79 test method. It is not only the LED but the whole SSL has to qualify all the tests.
For special purpose, it may be useful to determine the characteristics of SSL products when they are operated at other than standard conditions described in the approved method.
Photometric testing includes measurements of total radiant flux, luminous flux, Efficacy (lm/w), chromaticity, correlated color temperature (CCT), and color rendering index (CRI), Light Intensity Distribution (cd). Radiant flux, expressed in watts, is a measurement of the total power of electromagnetic radiation (light) emitted from the luminary or lamp. Luminous flux is a weighted measurement based on human visual perception.
The above measured parameters help to access the LED luminary quality and performance.