As new lighting source, LED has a lot of incomparable advantages: energy saving, environmental friendly, long service life, etc.. LED-related lighting fixtures received more and more attentions of consumers and producers. But LED light attenuation is also a big problem for LED manufacturers, which must be solved. Fast light attention impact the service life of LED lamps. Now, engineers faced bottlenecks in this area.
From current situations, LED light attenuation will become the biggest obstacle for LED lighting devices to enter the market of general lighting applications. What causes the light attenuation of LED lamps? Generally speaking, there are two major reasons:
1) Quality of LED chips: LED chips with bad quality will speed up the lighting attenuation; production process defects, especially defects in the packaging process will reduce the cooling effect of LED chips. Heat generated by LEDs cannot be conducted outward on time, leading to the continuous temperature increasing in LED chips.
2) Inappropriate applying conditions: normally, LED lamps use constant current power supplies, but some LEDs may be drove by constant voltage power supplies, which will cause long-term damages to G24 LED chips, speeding up the light attenuation; If the diving current exceeds the rated current, there will be more light attenuation, as well.
There are a variety of reasons may lead to LED light attenuation, heat dissipation is the most critical problem. Although many LED manufacturers spent a lot of energy and money on the secondary products (LED modules, LED applications), they still cannot maintain normal working conditions for a long time. The light attenuation of these secondary products is more serious than products with good cooling solutions. LED light attenuation has closed relations with the thermal resistance of LED chips, influences from silver plastics, the cooling effect of substrates, colloids and gold wires.
The quality of white-ray LED lamps can be said that a rather important factor for light attenuation. For example, same crystal 14mil white-ray LED chip: if using ordinary epoxy as bottom glue, packaging together with white glue and packaging glue, after 1000-hour constant working in 30 centigrade, the light attenuation is about 70%; if using D-type packaging glue, after 1000-hour constant working in 30 centigrade, the light attenuation is around 45%; if using C-type packaging glue, the light attenuation is only 12%; if using B-type packaging glue, the light attenuation is -3% (brighter than original products); if using A-type packaging glue, the light attenuation is -6% (even better).