Principle of LED lamp

LED (light emitting diode), light emitting diode, is a solid-state semiconductor device that can convert electric energy into visible light. It can directly convert electricity into light. The heart of LED is a semiconductor chip. One end of the chip is attached to a bracket, one end is the negative pole, and the other end is connected to the positive pole of the power supply, so that the whole chip is encapsulated by epoxy resin.

The semiconductor chip consists of two parts. One part is a p-type semiconductor, in which holes dominate, and the other end is an n-type semiconductor, mainly electrons. But when the two semiconductors are connected, a p-n junction is formed between them. When the current acts on the chip through the wire, the electrons will be pushed to the p region, where the electrons and holes compound, and then emit energy in the form of photons. This is the principle of LED light emission. The wavelength of light, that is, the color of light, is determined by the material forming the p-n junction.

LED can directly emit red, yellow, blue, green, green, orange, purple and white light.