LED display cooling reasons
With the recent years, LED technology as a new generation of lighting technology has been widespread concern, LED power increases, cooling problems will be more and more attention. Long-term observation by the researchers found that this is because the LED light failure or its life is directly related to its junction temperature, heat dissipation is very good junction temperature, life is short.
Unlike conventional incandescent and fluorescent lamps, their energy loss is large, but most of the energy is emitted directly through the infrared light, the heat of the light source less; and LED, in addition to the energy consumed as visual light, other energy conversion Became hot And because of the gradual development of electronic products to high density, high integration, Led products are no exception, so to solve Led thermal problems become today to improve Led performance, the development of Led industry, the main problem.
LED heating reasons:
LED fever because the added power is not all converted into light energy, but part of the conversion into heat. LED light efficiency is only 100lm / W, the electro-optical conversion efficiency of only about 20 to 30%. That is, about 70% of the electricity has become heat.
Specifically, the LED junction temperature is due to two factors:
1. The internal quantum efficiency is not high, that is, in the electron and hole recombination, and can not produce 100% of the photon, usually referred to as "current leakage" leaving the PN zone carrier recombination rate reduced. Leakage current multiplied by the voltage is part of the power, that is, into heat, but this part does not account for the main component, because the internal photon efficiency has been close to 90%.
2. The internally generated photons can not all be emitted to the outside of the chip and eventually converted to heat, which is the main reason, because this is called external quantum efficiency is only about 30%, most of them are converted into heat.
As mentioned above, although the incandescent light effect is very low, only 15lm / W or so, but it will almost all of the energy into light energy and radiation, because most of the radiation is infrared, so the light effect is very low , But it eliminates the heat problem.