What is the most important part of the LED light?

Update:27-07-2019
Summary:

The most important components of an LED lamp are: a sem […]

The most important components of an LED lamp are: a semiconductor wafer, a driver circuit, a lamp housing, and the like.
The semiconductor wafer consists of two parts, one part is a P-type semiconductor, in which the hole dominates, and the other end is an N-type semiconductor, which is mainly electrons here.
But when the two semiconductors are connected, they form a P-N junction. When a current is applied to the wafer through the wire, the electrons are pushed toward the P region. In the P region, the electrons recombine with the holes, and then the 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 (Light Emitting Diode), a solid-state semiconductor device that converts electrical energy into visible light, converts electricity directly into light. The heart of the LED is a semiconductor wafer with one end attached to a holder, one end being the negative pole and the other end connected to the positive pole of the power supply, so that the entire wafer is encapsulated by epoxy.
Drive circuit. The main function of the drive circuit is to convert the AC power into a DC power supply, and simultaneously complete the voltage and current in accordance with the LED to drive the matching components. If the drive circuit is not normal, it will affect the normal operation of the entire LED lamp.
The outer casing of the lamp. The brightness of the LED lamp is very strong, and it is easy to make the light energy into heat energy, making the LED lamp very hot. If the LED lamp can not dissipate heat as quickly as possible, its life will be greatly shortened.

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