How to choose the glue in the LED package LED use, loss of photons produced by radiative recombination generated during launch out, mainly includes three aspects: 1, the internal structure of the chip defects and absorbing materials; 2, photons emitted interface due to refraction loss due to the reflection rate difference; 3, and reflection losses due to the angle of incidence greater than the critical angle of total reflection caused. Therefore, many light not emitted to the outside from the chip. Coating a surface of the chip by a relatively high refractive index of silica is between the die and the air, thus effectively reducing the loss of photons at the interface to improve the light extraction efficiency. Furthermore, the role of the silicone chip also includes mechanical protection, stress relief, and as a light guide structure to enhance heat dissipation to reduce the junction temperature of the chip and improve the LED performance. To improve the reliability of the LED package, a silica gel also has low moisture absorption, low stress, anti-aging properties. The commonly used include epoxy and silicone encapsulants. Research shows that increasing the refractive index of silica gel which can effectively reduce the refractive index caused by a physical barrier photon loss and improve external quantum efficiency, but the performance is affected by the ambient temperature silica greater. As the temperature increases, thermal stress inside the silica gel to increase, resulting in lower refractive index of silica, thus affecting the efficiency of the LED light and the light intensity distribution. However, the overall performance is better than silicone epoxy resin, widely used in high-power LED package. If you want to know more information, please visit (led glue http://www.rtvmifengjiao.com) Website