Packaging element that affects light extraction efficiency: reflection treatment

LED is called the fourth-generation light source or green light source in the landscape light factory. It has the characteristics of energy saving, environmental protection, long life and small size. It is widely used in various indications, displays, decorations, backlights, general lighting and city night scenes. According to the different functions, it can be divided into five categories: information display, signal lamp, car lamp, LCD backlight and general lighting. u003cbru003e u003cbru003e u003cbru003e u003cbru003e u003cbru003e u003cbru003e Conventional LED lamps have disadvantages such as insufficient brightness, which results in insufficient penetration. Power LED lamps have the advantages of sufficient brightness and long service life, but power LEDs have technical problems such as packaging. The following briefly analyzes the factors that affect the light extraction efficiency of the power LED package. u003cbru003e u003cbru003e u003cbru003e u003cbru003e u003cbru003e u003cbru003e Packaging components that affect light extraction efficiency: reflection treatment u003cbru003e u003cbru003e u003cbru003e u003cbru003e u003cbru003e u003cbru003e There are two main aspects of reflection treatment, one is the reflection treatment inside the chip, and the other is the reflection of light by the packaging material. Through internal and external reflection processing, the proportion of light emitted from the chip is increased and the internal absorption of the chip is reduced. Improve the luminous efficiency of high-power LED products. In terms of packaging, power LEDs and power chips are usually assembled on a metal support or substrate with a reflective cavity. The bracket-type reflective cavity is usually electroplated to improve the reflection effect, and the substrate-type reflective cavity is usually polished. In the method, if possible, electroplating treatment will be carried out. However, the above two treatment methods are affected by the precision and process of the mold, and the treated reflective cavity has a certain reflection effect, but it is not ideal. u003cbru003e At present, due to insufficient polishing accuracy or oxidation of the metal coating, the reflection effect of the substrate-type reflective cavity produced in China is poor. This causes a lot of light to be absorbed after hitting the reflective area and cannot be reflected to the light-emitting surface as expected, resulting in low light extraction efficiency after the final packaging.