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How LEDs Work

 How LEDs work


How the LED diode works

LEDs were introduced as a practical form of lighting in 1962, however, there is very little information concerning how they work on the internet, hopefully the following article will help you understand how LEDs work.

how leds work

An LED is one of the simplest forms of semiconducting diode. A semiconductor is basically a material that will conduct electricity under certain circumstances and not under others.

I will now remove the outer shell of a typical LED that you will find in many household electronic devices (all images are high res so click to zoom in) –

how leds work

On the left is the positive lead coming from the positive battery terminal and on the right is the negative lead from the negative terminal. If we now zoom in a little closer we will be able to see the light emitting components on the top section of the LED up close –

how leds work

The positive connection on the left is simply that – a connection jumping from the positive lead over to the semiconductor material, it has to jump like this so it does not short out on the negative lead anywhere, which would result in the LED not working. On the right you can see the semiconductor diode, it consists of two sections of differing material placed side by side to each other.

The part of an LED that most concerns us in the semiconducting diode, it is the part that makes the light, i will remove all of the other parts of the LED except for the semiconducting diode:

how leds work