Light-emitting diode facts for kids

Blue, green and red LEDs.

Green SMD LED.

A light-emitting diode (LED) is a small electronic part that makes light when electricity passes through it. Think of it like a tiny light bulb, but much more advanced! LEDs are very popular because they last a long time and are tough. They don't break easily like old-fashioned light bulbs.

LEDs can create many different colors of light. They are also very good at saving energy. Most of the electricity they use turns into light, not wasted heat. This makes them very efficient.

An LED is a special kind of diode. A diode is a device that lets electricity flow in only one direction. When electricity flows the right way through an LED, it glows. This glowing effect is called electroluminescence.

The color of the light an LED makes depends on the materials it is made from. Some LEDs make visible light that we can see, like red, green, or blue. Others make light that we cannot see, like near-ultraviolet or infrared light. The color also affects how much electricity the LED uses.

Some white LEDs are actually made of two or three different colored LEDs inside. Other white LEDs use a single-color LED, usually blue, combined with a special material called a phosphor. This phosphor changes the blue light into white light.

LEDs are used everywhere today! You can find them as indicator lights on your electronic devices, like your phone charger or computer. They are used in bright advertising signs, in the brake lights of many cars, and in TVs. More and more, people are using white LED light bulbs to light up their homes. Even though white LEDs might cost a bit more at first, they save money over time because they last longer and use less electricity.

It's important not to confuse LEDs with LCDs. LEDs make their own light, while LCDs work by blocking light. However, some screens use both technologies. For example, many LCD screens use LEDs behind them to light up the display.

Many modern LEDs are designed using surface-mount devices (SMD). This means they can be made very, very small.

Types of LEDs

There are different kinds of LEDs, each with special features:

• Organic LEDs (OLEDs): These LEDs use organic (carbon-based) materials to make light. They are often used in flexible screens, like those on some smartphones and TVs.
• Crystal LEDs (MicroLEDs): These are very tiny LEDs that are packed closely together. They can create very bright and clear displays, often seen in large video walls or future TVs.

Where We See LEDs

LEDs are used in many everyday items and places:

• Indicator Lights: The small lights on your electronics that show if they are on or off.
• Displays: In calculators, digital clocks, and large outdoor screens.
• Lighting: For homes, offices, and streetlights, saving energy and lasting a long time.
• Vehicles: In car headlights, taillights, and interior lights.
• Traffic Signals: The red, yellow, and green lights at intersections often use LEDs.
• Special Uses: In things like miner's lamps, stage costumes, and even for growing plants indoors.

Images for kids

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  A close-up view of a surface mount LED.

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  A modern LED light bulb that screws into a regular lamp socket.

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  This shows how early LEDs looked, recreating an experiment from 1907.

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  An early LED from 1962, made by Texas Instruments.

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  The LED display of a TI-30 calculator from around 1978.

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  Blue LEDs on a circuit board.

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  An RGB LED, which can make red, green, and blue light.

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  A diagram showing how a white LED combines blue light with light from a phosphor.

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  LEDs come in many shapes and sizes. The plastic color doesn't always match the light color.

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  Tiny surface mount LEDs compared to a larger, traditional LED.

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  A very small RGB surface mount LED, showing its tiny parts.

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  Powerful LEDs used for bright lighting.

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  Another example of an RGB surface mount LED.

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  A close-up of an LED display, like those used on name tags.

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  LEDs used as daytime running lights on a car.

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  Traffic lights using red and green LEDs.

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  An LED light used by miners for safety.

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  The Vincent Thomas Bridge in Los Angeles lit up with blue LEDs.

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  A cool costume with built-in LEDs for performers.

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  Wallpaper with tiny LEDs that light up.

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  A large LED screen behind a DJ.

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  A seven-segment LED display, often seen in digital clocks.

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  An LED panel used to help plants grow in experiments.

See also

In Spanish: Led para niños