The light-emitting diode of LED lamp beads is a solid-state semiconductor device capable of converting electrical energy into visible light, which can directly convert electricity into light.

LED is the abbreviation of light emitting diode (light emitting diode) in English. Its basic structure is a chip of electroluminescent semiconductor material, which is cured on the bracket with silver glue or white glue, and then the chip and the circuit board are connected with silver or gold wires. The surrounding area is sealed with epoxy resin to protect the internal core wire. Finally, the outer shell is installed, so the shock resistance of the LED lamp is good. The application field involves the production of daily household appliances and machinery such as mobile phones, table lamps, and home appliances.
    
The heart of the LED is a semiconductor wafer. One end of the wafer is attached to a bracket, one end is the negative electrode, and the other end is connected to the positive electrode of the power supply, so that the entire chip is encapsulated by epoxy resin.

A semiconductor wafer consists of two parts, one is a P-type semiconductor, where holes dominate, and the other end is an N-type semiconductor, which is mainly electrons. But when these two semiconductors are connected, a P-N junction is formed between them. When a current is applied to the chip through a wire, the electrons are pushed to the P region, where the electrons and holes recombine, and then energy is emitted in the form of photons. This is the principle of LED light emission. The wavelength of light, which is the color of light, is determined by the material that forms the P-N junction.

LED lamp beads luminous characters are composed of light emitting dot matrix one by one, each dot matrix element is composed of red, green and blue light emitting diode chip sets packaged together, as long as the voltage of the three color chips is controlled The ratio of the current can be changed to change the color of each dot matrix element. By controlling the driving voltage and current of all the unit dot matrix by the computer, the display of images and characters and color changes can be realized.