What is LED?
LED is the abbreviation of English light emitting diode (LED). Its basic structure is an electroluminescent semiconductor material, placed on a leaded shelf, and then sealed with epoxy resin to protect the internal heart. The role of the line, so the LED's seismic performance is good. In general, LEDs are made of III--IV compounds such as GaAS (Gasenide), GaP (gallium phosphide), GaAsP (gallium gallium arsenide) GaN (GaN), and light emitting diodes. The core part is a wafer composed of a P-type semiconductor and an N-type semiconductor. There is a transition layer between the P-type semiconductor and the N-type semiconductor, which is called a PN junction.
In the P-N junction of some semiconductor materials, the injected minority carrier and the majority carrier compound will release the excess energy in the form of light, thereby converting the electrical energy directly into light energy. The reverse voltage of the P-N junction makes it difficult for minority carriers to inject, and therefore does not emit light. This kind of diode made by using the principle of injection electroluminescence is called light emitting diode, collectively referred to as LED. When it is in the forward working state (ie, the forward voltage is applied at both ends), the current flows from the anode of the LED to the cathode, and the semiconductor crystal emits light of different colors from the UV-IR. The intensity of the light is related to the current.