Process structure of white LED and white light source. For general lighting, in terms of process structure, white light LEDs are usually formed by two methods. The first is to use “blue technology” and phosphors to form white light; the second is a variety of monochromatic light mixing methods.
Both of these methods have successfully produced white light devices. The first method of generating white light is shown in Figure 1. The LED GaM chip in the picture emits blue light (λp=465nm), which is packaged with YAG (yttrium aluminum garnet) phosphor, and emits when the phosphor is excited by blue light. Yellow light, as a result, blue light and yellow light are mixed to form white light (the structure of the LED is shown in Figure 2). The second method uses chips with different colors of light to be packaged together, and white light is generated by mixing the colors of light.
