Car LED light lumen attenuation is the weakening of the light signal during transmission. Car led light made by global leading manufacturers at the present stage have lumen attenuation in different grades after used for a period of time and this phenomenon also exists in high power LEDs. Lumen attenuation is directly related to the temperature, and is mainly determined by the chip, phosphor used and the packaging technology. Then, what causes car led light attenuation? At present, lumen attenuation has become the chief problem for white LED to march into civil lighting field. There are two main problems that cause car led light lumen attenuation:
Ⅰ The quality of the car led light product itself
1. The production technology has some defects. car led light chips may be over heated and thus causing chip attenuation more serious. If the heat generated by car led light chips can not be exported out of the chip smoothly by the PINs,
2. The brightness of car led light will attenuate quickly if the quality of the adopted auto led chip is not good.
Ⅱ The operating condition
1. If the driving current is larger than the rated value, car led light lumen may easily get attenuated.
2. car led light should be drove by constant current, if drove by voltage, the led light lumen attenuation will be caused.
Among the various causes of car led light products lumen attenuation, “heat” is the pivotal one. the heat dissipation effect of the substrate and golden wire problems are also related closely to car led light lumen attenuation. Many manufacturers pay little attention to the heat dissipation of the products, leading to a much more serious lumen attenuation compared to those products that dissipate heat properly. Besides, thermal resistance of the car led light chip itself, silver colloid,