Led Bulb working Principle

Working principle of Led

A led bulb is a semiconductor device that emits light when electricity passed through it. The colour of the light depends on the material used in the led making.

With the help of chemical compounds like Gallium Arsenide and Gallium Phosphide, a Led bulb that gives red, green, yellow, and orange lights are produced. Displays in digital watches and calculators, street lamps, traffic signals, etc are some examples of LED.

A seven-segment display is a display used to display numbers and text. It is used in digital meters, digital clocks, microwave ovens, etc. It consists of 7 segments of LED in the form of the digit 8. These seven LEDs are named as a,b,c,d,e,f, and g. An extra 8th LED is used to display a dot.

Seven segment display using led, used in calculator, traffic signals
Seven segment display using Led

Merits of a LED bulb

  • The LED bulb does not have a filament, so there is no loss of energy in the form of heat and as a result, it is cooler than the incandescent bulb.
  • It has a lower power requirement than fluorescent lights.
  • It is not harmful to the environment as it does not produce heat.
  • Many colour lights can be produced.
  • It is cost-efficient and energy-efficient.
  • Mercury and other toxic materials are not used in Mercury.
  • To overcome the energy crisis, we need to use more LED bulbs.

LED Television

  • LED Television is one of the important applications of LED.
  • It is actually an LCD panel with when LED backlight as an LCD panel does not produce light.
  • An array of LEDs act as pixels.
  • LED emitting white light is used in Monochrome tv (black and white tv)
  • Red, Green, and Blue (RGB) LEDs are used in colour television.
  • The first LED television screen developed by James P Mitchell in 1977, it had a monochromatic display.
  • In 2009, Sony introduced the first commercial LED television.

Advantages of LED television

  • Bright Picture Quality.
  • It is thin.
  • Uses less power.
  • It has more life span.
  • It is more reliable.
* * All the Notes in this blog, are referred from Tamil Nadu State Board Books and Samacheer Kalvi Books. Kindly check with the original Tamil Nadu state board books and Ncert Books.