What are LEDs?
As the name suggests, a LED (Light Emitting Diode) is basically a small light producing device that comes under “active" semiconductor electronic components. It’s quite comparable to the normal general purpose diode, with the only big difference being its capability to emit light in different colors. The two terminals (anode and cathode) of a LED when connected to a voltage source in the correct polarity, may produce lights of different colors, as per the semiconductor substance used inside it.
From your cell phone to the large advertising display boards, the wide range of applications of these magical light bulbs can be witnessed almost everywhere. Today their popularity and applications are increasing rapidly due to some remarkable properties they have. Specifically, LEDs are very small in size, consume very little power, and are able to produce extremely high light intensity outputs.
Unlike age-old incandescent bulbs, LEDs does not require red hot filaments to produce light. Rather it’s more effectively done through the passage of electrons and due to the band gap effect of its semiconductor material.
Moreover, the heat generated in the process is negligibly small, thus there is no threat to the ever rising global warming problem, and LEDs are fast emerging as a better lighting solution compared to the other forms of modern lighting devices like FTLs and CFLs.
LEDs that can emit lights invisible to the naked eye in the infrared and ultra violet range are also produced largely and find major application in remote control devices. Here we will discuss the functioning of the more popular ones, i.e. the visible light emitting type of LEDs.
Let’s move on and study how LED light bulbs work.