What is the luminous principle of light -emitting diode LED lighting fixture? LED (Light Emitting Diode), luminous diode, is a solid semiconductor device, which can directly convert electricity into light. The heart of the LED is a semiconductor chip. The chip is fixed on a bracket. One end is the negative electrode. The other end is connected to the positive electrode of the power supply, so that the entire chip is packaged by epoxy resin.

Semiconductor chips are composed of two parts, one is a P -type semiconductor. In it, the acupuncture points are dominated. The other end is N -type semiconductor. It is mainly electron here. But when these two semiconductors are connected, a P-N knot is formed between them.

When the current passs through the wire to act on this chip, the electrons will be pushed to the P area. In the P area, the electron and acupoints will be compounded, and then the energy will be emitted in the form of a photon. This is the principle of LED glowing. The wavelength of light is the color of light, which is determined by the material that forms the P-N knot.

The original LED was used as an instrumental light source for instruments. Later, various light -colored LEDs were widely used in traffic signal lights and large -area display screens, which produced good economic and social benefits. Take a 12 -inch red traffic signal light as an example. In the United States, the 140 -watt -incandescent lamp is used as a light source in the United States. It produces 2000 lumen white light.

After red filter, the light lost 90%, leaving only the red light of 200 lumens. In the newly designed lamp, Lumileds uses 18 red LED light sources, including circuit loss, and consumes a total of 14 watts to produce the same light effect. Car signal lights are also important areas of LED light source applications.

For general lighting, people need white light sources. The development of white light in 1998 was successful. This LED is made of GAN chips and pyrine pitch (YAG). GAN chip hair blue light (λp = 465nm, WD = 30nm), and the CE3+YAG fluorescent powder containing CE3+made of high -temperature sintering emits yellow light after this blue light is excited, and the peak value is 550nm. The Blu-ray LED substrate is installed in the bowl-shaped reflex cavity, covering the thin layer of the resin mixed with YAG, about 200-500nm.

The Blu -ray part of the LED substrate is absorbed by the fluorescent powder, and the other part of the blue light is mixed with the yellow light emitted by the fluorescent powder to get white light. For Ingan/YAG white LED, by changing the chemical composition of YAG fluorescent powder and regulating the thickness of the fluorescent powder layer, you can get a variety of white light of 3500-10000K. This method of stimulating fluorescent powder through Blu -ray LED to get white light, with simple structure, low cost, and high technical maturity, so it is used most.