Light Emitting Diode or LED is an electronic semiconductor component. Flows of current in diode is one direction, it emits visible light, infrared or UV Rays. Primarily Light Emitting Diode or LED was only used as indicators as it consumes very less power, but with time, Light Emitting Diode are being used as a next generation replacement of CFL and Halogen lamps too.

Technology behind Light Emitting Diode or LED

The basic structure of Light Emitting Diode is corresponding to that of a pn semiconductor diode, Light Emitting Diode therefore possess the same basic features as the latter. A big difference is in the semiconductor material used. While non-luminous diodes are made ​​of silicon, less commonly germanium, the starting material for Light Emitting Diode usually a gallium compound .

The semiconductor crystal of many Light Emitting Diode is on the bottom of a cone-shaped depression in a metal holder. The inner sides of the recess act as a reflector for the the light generating crystal. The solder joint is one of the two electrical terminals of the crystal. At the same time it takes up the waste heat, which arises because the semiconductor crystal converts only a part of the electrical power to light. Unlike other electronic components, lead is not the wire but tinned copper or tinned steel is used. The thermal conductivity of steel is relatively small. Thus, the semiconductor crystal is in the soldering of the component to a printed circuit board is not overheated.

Usage of Light Emitting Diode

Light Emitting Diode mostly comes as with polymer capped. With bright the Light Emitting Diode, glass or metal housing are used. The usage of Light Emitting Diode has been increased due to less energy consumption, high life time (15,000 to 30,000 hours). The color of a light emitting diode depends essentially on the band gap from the used semiconductor material. Currently Light Emitting Diode as a source of light or as a replacement of neon bulb are in use. Here is a shortlist of usages of Light Emitting Diode.

• Displays such as the seven-segment displays or matrix displays
• Another application of Light Emitting Diode in the range of lighting and its use as a lamp.
• Appropriate LCD displays are often colloquially termed as LED Display.
• Light Emitting Diode by comparison with the flash bulbs more efficient and produces clear line, often used in laser technology as the pump source.
• From a CFL replacement to Car Lamps, Light Emitting Diode are becoming more prominent.