Friday, December 27, 2013

What is an LED?

There is so much buzz about LED lighting these days that it is enough to make you wonder just what in the world is so hot about such lighting. Think about it, it is just another source of light so what makes this so special? 

The light in most homes is produced by incandescent bulbs. Inside the bulb is a very thin and fragile, coiled tungsten filament. For the bulb to produce light an electric current is passed through a conductor and the tungsten is heated to the point at which it gives off light. Unfortunately, these bulbs are not very energy efficient; roughly 10% of the energy is used to make visible light.

How do LED lights work? 
The structure of the LED light is completely different than that of the light bulb. Amazingly, the LED or light-emitting-diode has a small and simple structure. The beauty of this structure is that it allows for assembly into many different spaces. 
The LED is actually a diode that emits light. A diode is a semiconductor device covered with a lens that allows current to flow in only one direction.  When electricity is passed through the diode the atoms in one material (within the semiconductor chip) are excited to a higher energy level. The atoms have too much energy and need to release that energy. The energy is then released as the atoms shed electrons to the other material within the chip. During this energy release light is created. 
The color of the light emitted from the LED is a function of the materials that form the chips. Common LED colors include amber, red, green, and blue. There is actually no such thing as a “white” LED. To get white light, different color LEDs are mixed or covered with a phosphor material that converts the color of the light.

What are the advantages of LED lights? 
LED lights have a variety of advantages over other light sources:
  • Environmental friendly
  • Energy efficient
  • Low-voltage and current requirements
  • Low radiated heat
  • Durable (resistant to shock and vibration)
  • No UV Rays
  • Long life
  • Controllable
What are they used for?
LEDs are mainly used for two things: illumination and direction. Different LED lights can be used for different things like TV sets, lights for cars, and even to light up a home. Another good use for LEDs  is to illuminate LED signs for businesses and other organizations. Projected to reach $30 billion by 2025, the LED lighting industry has come a long way from its initial use as a humble indicator light.