How long is life span of LED? Can it really reach 50000 hours?

When we talking about lifespan of LED, it refers to L70 which is when the lumen maintenance is 70% of the original level. Generally it is not convenient to test a LED lamp continuously for 50000 hours. So generally the lab will using accelerated aging test method to get the lumen depreciation situation after 6000 hours or 10000 hours , together with Decay curve fitting, to evaluate lifespan of LED. Currently there are two main standards of testing lumens depreciation, they are LM79 and TM-21. When the test reports meet standards of 50000 hours requirement, we can state the life span of the LED lamp reach 50000 hours.

What’s the main parameters of LED ?

1, For lighting part, they are Lumen output, Lumen efficacy, Correlated color temperature, CRI, lumen maintenance

2, For Electric part, they are forward voltage, backward voltage, rated power

3, For Thermal part, they are thermal resistance, junction temperature, color tolerance

What is Electrostatic damage? Which kind LED is easy to be damaged by them?

Electrostatic is the electric charge which is a stationary state. There are both positive electrostatic and passive electrostatic. When they are connected to zero potential staff or staffs which have potential difference, the electronic charge will have charge transfer. The crystal device which have low anti-electrostatic ability is easy to be damaged by it.

What is junction temperature?

It is temperature of PN junction, or the highest junction temperature. It is the highest temperature which the PN junction can withstand. Generally it is 130 degree.