The end voltage of the PN knot constitutes a certain potential barrier. When the bias voltage decreases when the positive bias voltage is added, most carrier in the P and N areas spread to the other party. Because the electronic migration rate is much greater than the empty acupoint migration rate, a large number of electronic spreads to the P area, forming an injection of a minority carrier of the P area. These electrons are compounded with the cave on the price, and the energy obtained during composite is released in the form of light energy. This is the principle of PN glowing.

LED lamp bead characteristic

1. Voltage: LED lamp beads use a low voltage power supply, the power supply voltage is between 2-4V, which vary according to the product, so it is a high-voltage power supply than a high-voltage power; more secure power supply is especially suitable for public places;

2. current: The working current is 0-15mA, and the brightness becomes brighter with the increase of the current

3. Efficacy: The consumption of energy is 80%lower than the incandescent lamp with the same light.

4. Applicability: Very small. Each unit LED piece is a square of 3-5mm, so it can be prepared into various shapes of devices, and it is suitable for vulnerable environments.

6. Response time: The response time of the incandescent lamp is milliseconds, and the response time of the LED light is nanosecond.

7. For environmental pollution: no harmful metal mercury.

8. Color: Change the current can change color. The light -emitting diode is convenient to adjust the structure and band gap of the material through chemical modification methods to achieve red, yellow and green orchid orange multi -color light. For example, a small current is a red LED. As the current increases, it can become orange, yellow, and finally green.