Basic Knowledge of LED

Light Emitting Diode is a semiconductor device which can emit light energy in a certain colour. LED is fundamentally different from traditional light emitting sources such as fluorescent, gas discharge lamps and incandescent. LED do not use gas or filament also LED has no glass bulbs.
There is no fear of failure-prone moving parts.


History

Let's have look on LED History. In 1962 Nick Holonyak developed first red LED at G.E. Throughout the 60’s only red LED were available so only the red LED was used on electronic devices like a small indicator. Green and yellow LED were developed in the next decade i.e. early 70’s. As tree colours were developed, they were used in traffic signals, watches, exit signs and other electronic stuff. In 1996 Phosphor white LED were developed by combining blue or ultraviolet LED with a phosphor coating which can produce white light. The output level of 100 lumens was possible by 2005 also there were a variety of shades of white light LED. After that, there was a competition between LEDs and conventional white light sources. It is expected by The Department of Energy that, by 2025 LED technology to become the preferred method if lightning in homes and offices.



Advantages

LED's are very efficient compared to traditional resources such as CFLs, fluorescent tubes and incandescent. Even the quality of white light of LEDs is very good and consistent compared to CFL’s. Even the life of LEDs is longer than other resources. The fixtures of LED are directorial which allows more efficient optics.One of the major advantages of LEDs is its cost is getting dropped by 20%/year and its light output is improved by 35% per year. Also, LEDs are Infrared radiation, ultraviolet rays and Mercury free. LEDs can be operated in an extremely cold environment too also vibrations cant affect them i.e. LEDs can withstand any impact.