What are Light-Emitting Diodes?

Light-Emitting Diode is a semiconductor device which emits light when electric current flows through it.

What are Light-Emitting Diodes?
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About Light-Emitting Diodes

  • A diode is an electronic component which has two points of contact, or terminals, called its anode and cathode.
  • A diode’s primary purpose is to allow current to flow in only one direction.
  • An LED is a semiconductor device which emits light when electric current flows through it.
  • It can produce all three primary colours – red, green, and blue – different LEDs can be combined on a display board to produce a large variety of colours.

Advantages of LED

  • Energy Efficiency: It requires far less electricity to produce the same light as incandescent bulbs. LEDs use approximately 75-80% less energy than traditional incandescent bulbs
  • Durability: LED bulbs are highly durable and resistant to shocks, vibrations, and temperature fluctuations.
  • Instant Illumination: It provides instant illumination without the warm-up period required by incandescent bulbs.
  • Heat Generation: LED bulbs generate very little heat, making them safer to handle and more efficient in terms of energy utilization. 
  • Environmental Impact: LEDs have a significantly lower environmental impact compared to incandescent. The energy efficiency and longer lifespan result in reduced greenhouse gas emissions and less waste.

What are the Applications of LEDs?

  • LEDs have several applications in industry, consumer electronics, and household appliances: from smartphones to TV screens, from signboards to ‘feeding’ plants light in greenhouses, from barcode scanners to monitoring air quality.

Q1) What is a semiconductor?

It is a substance that has specific electrical properties that enable it to serve as a foundation for computers and other electronic devices. It is typically a solid chemical element or compound that conducts electricity under certain conditions but not others.

Source: What are light-emitting diodes and why are they prized as light sources? | Explained

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