what exactly do you mean by led ?

 

What do you mean by led ?

A very basic introduction to the workings of a light-emitting diode.

In its most basic sense, the simplest definition, an LED ( led full form) is an electronic device that emits light when an electric current is moved through it. The light is produced when the particles carrying electrons , holes and electrons (known in the form of holes and electrons) are incorporated into the semiconductor's materials.

Since light is produced within the semiconductors, they can be described in terms of solid-state technology. Solid-state lighting is a term that also comprises organic LEDs (OLEDs) sets this technology of light from other sources using heated filaments (incandescent and tungsten lamp halogens) (or gas discharge) (fluorescent lamps).

Different colors
Within the semiconductor of the LED the electrons as well as the holes are contained within energy bands. This separation (i.e. that is the bandgap) is the key to determining the energy level of the photons (light particles) which escape from the LED.

The energy of the photon determines the wavelength of light that is emitted and the consequent hue. Different semiconductor materials with various bands emit different shades of light. The exact frequency (color) can be altered by changing the structure of the light emitting area or the active region.

LEDs are composed of semiconductor compounds comprised of elements of groups III and V on the periodic table (these are also known as III-V-based materials). Examples of III-V materials commonly used in the production of LEDs include gallium arsenide (GaAs) and gallium Phosphide (GaP).

In the early 90s, LEDs were available in a small selection of colors . In particular, commercial blue and white LEDs were not being used. Introduction of LEDs made of gallium Nitride (GaN) technology expanded the color range and allowed numerous new possibilities.

Main LED materials
The principal semiconductor materials that are used to make LEDs are:

• Indium Gallium Nitride (InGaN):blue, green , and ultraviolet high-brightness LEDs.
• Algalium gallium Phosphide (AlGaInP):yellow, bright red and orange high-brightness light sources
• Algalium gallium arsenide (AlGaAs):red and infrared LEDs
• Gallium Phosphide (GaP):yellow and green LEDs

Learn About LED Lighting

• The Basics
  • What are LEDs and how do they work?
  • Lifetime of LED lighting products
  • Where to use LED Bulbs
  • LEDs and Heat
• How is LED lighting different?
• What are the reasons for choosing the ENERGY STAR(r) qualified LED products for lighting?

The Basics of LED Lighting

What are LEDs and how do they work?

LEDstands for light emitting diode. LED lighting products create light that is up to 90 % more efficiently than conventional light bulbs. What is their purpose? A current of electricity flows through a microchip. The microchip emits light to those tiny lights that are referred to as LEDs. This results in visible lights. To prevent problems with performance the heat produced by LEDs is absorbed by a heat sink.

Lifetime of LED Lighting Products

The practical life of LED lighting equipment is different from that of other lighting sources, including incandescent and Compact Fluorescent Lamp (CFL). LEDs typically do not "burn out" or fail. Instead they suffer from 'lumen depreciation' which occurs when the LED's brightness decreases gradually over. In contrast to bulbs that use incandescents, LEDs "lifetime" is established on an estimate of when the the brightness decreases by 30 percent.

How are LEDs Used in Lighting

LEDs are included in fixtures and bulbs for general lighting purposes. Small in size, LEDs provide unique design opportunities. Certain LED bulbs can appear like traditional light bulbs and are more similar to the design of traditional lighting bulbs. Certain LED lighting fixtures might have LEDs inside them for permanent illumination sources. They also offer hybrid solutions which use a different "bulb" or replaceable light source design and created specifically for a particular fixture. LEDs offer a great opportunity for innovation in lighting forms and are able to be employed in many different applications in comparison to traditional lighting technologies.

LEDs and Heat

LEDs employ heat sinks to absorb the heat generated by the LED, and then disperse it into the environment. This stops LEDs from overheating in the process of burning. The control of temperature is typically the key factor in the performance of LEDs throughout its lifespan. The higher temperatures the LEDs operate at and the greater the intensity of light's performance will diminish and the more time-consuming its use will be.

LED products utilize a range of different designs for heat sinks and various configurations to handle the heat. Today, advancements in materials allow manufacturers to create LED lamps that have shapes akin to the dimensions and shapes conventional incandescent bulb. In spite of the heat-sink design, the majority of LED products that have earned recognition with ENERGY STAR have been tested to verify that they are able to handle the heat and ensure that the light output is sufficient until the end of their life.

Read more about it here. led full form