How LED Work? (Know with Images)

More than 200 years ago, electric light was invented. Since then, they have been in use largely. The electric light works when electricity is converted to light along with some little amount of heat. The two most common types of electric lights are used today.

They are incandescent lights and LED lights. Incandescent lights are the oldest type of electric lights, and LED lights, also known as light-emitting diodes, are the new forms of electric lights.

What Is a Led (light-Emitting Diode)?

A LED or light-emitting diode is a semiconductor device. This device radiates incoherent narrow-spectrum light. It happens when it is electrically biased toward the forward direction. This entire phenomenon is known as a form of electroluminescence. 

The color emitted by the device depends entirely on the chemical composition of the device’s semiconducting materials. It can be near ultraviolet, visible, or infrared. The first ever practical visible-spectrum light-emitting diode was done in 1962 at the University of Illinois at Urbana-Champaign. Nick Holonyak Jr conducted this practical.

How Do LEDs Work?

An LED (light-emitting diode) is made of semiconductor materials with positive – p-type and negative n-type materials. The two types make the LED light up. Light is emitted from the LED when the electric current moves from the p-type to the n-type material.

Physical Function of LEDs (Light-Emitting Diode)

LED is considered a special type of semiconductor diode. Like any normal diode, it is made of a semiconducting material chip stuffed with impurities for creating a structure known as a p-n junction. Charge carriers i.e. the holes and electrons, flow into the p-n junction from electrodes with multiple types of voltages.

In the process, when an electron comes in contact with a hole, the entire process falls into a much lower energy level. This, in return, releases energy in the formation of a photon.

Light emission of LEDs 

The wavelength of light that is emitted and, henceforth, its color depends entirely on the band gap energy of the various materials, thus forming the p-n junction. Any normal diode made of germanium and silicon radiates invisible far-infrared light.

On the other hand, the several components used for the LEDs have band gap energies that correspond with the nearest infrared, near-ultraviolet, or visible light.

Uses of LEDs

 LEDs (light-emitting diodes) find applications in several fields. This includes optical communication, security systems and alarms, robotics, remote-controlled operations, etc. Led’s finds usage in various platforms because of the long-lasting capability, swift response time, fast switching capabilities, and low power requirements. Some standard usages of LEDs are:

TV back-lighting

Used in displays

Dimming of lights

Used in Automotives

Types of LEDs 

The different types of LEDs (light-emitting diodes) that are used largely  and designed using semiconductors are :

High-Power LEDs

Flash LED

Miniature LEDs

Lighting LED

Bi and Tri-Color

Alphanumeric LED

Red, Green Blue LEDs

Facts About LeDs 

A small reflector is used around the semiconductor crystal of the LED, enabling it to emit bright light.

There are two legs in a LED that is connected to a circuit. These legs, also known as ‘leads,’ help pull the heat away from the circuit of the LED.

The legs or the leads of a LED are not the same. One is longer, and the other one is shorter. The longer leg is called an anode, while the shorter leg is called a cathode.

The voltage range of a LED is between 1.5 volts to 3.6 volts.

At the end of this article, we learned about LED, how it works, its physical functions, and light emission factors. We also got information about the types of LEDs available and what are the usages of the LEDs. You can visit our website to learn more about such wonderful facts.

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