The shortcomings of LED panel lights mainly exist in the problems of poor uniformity of light emission and short life of enclosed materials. Although the expected advantages of white light LEDs cannot be used, but from the perspective of demand, this is not only general The use of lighting, but with the widespread application of mobile phones, tv, automobiles and other industries, making the most appropriate development of white LED technology research results have been widely concerned.
There are currently two major directions for improving the luminous efficiency of white LEDs. One is to increase the area of the LED chip to increase the amount of light emitted. The second is to package several small chips together under the same module by increasing the chip area to increase the amount of light. Although the area of the LED chip is enlarged, it can obtain much higher brightness, but because of the large area , There will be counterproductive phenomena in the application process and results. Therefore, in response to this problem, some LED manufacturers have improved the surface of the chip based on the improvement of the electrode structure and the structure of the flip chip to achieve a luminous efficiency of 50lm/W.
For example, in the flip-chip package of an LED panel lamp, since the light-emitting layer is very close to the light guide package, the electrode will not be shielded when the light of the light-emitting layer is emitted to the outside, but the disadvantage is that the generated heat is not easily dissipated.
It is not after improving the chip surface, plus increasing the chip area, that the brightness can definitely be increased quickly, because when the light diffuses from the inside of the chip, these improved parts in the chip cannot be reflected, so there will be a little bit of light extraction. Limitation. According to calculations, the LED chip size that best exerts light efficiency is about 7mm2.
Of course, this approach will also cause some unavoidable problems. For example, because multiple LEDs are packaged on the same module, some insulating materials must be placed in order to avoid short circuits between LED chips. It will increase a lot of costs. But from the perspective of environmental protection, this has more advantages than disadvantages.
