LEDs are light emitting diodes. These are electronic components that convert electrical energy directly to light through the movement of electrons within the material of the diode. LEDs are important because due to their efficiency and low energy, they are beginning to replace most conventional light sources.

The term solid state lighting is used because the electronics produce light directly from solid materials in which the electrons are embedded. This is unlike other technologies, for example fluorescent technology, which requires a gaseous discharge medium to initiate production of light.

LED technology is constantly changing. Rapid innovation continues to improve the performance of LED on an almost daily basis. Future-proofing of LED modules allows luminaire manufacturers to switch from one generation to the next improved generation without major retooling or changes in luminaire design, offering backward compatibility with drivers.

LED chips are mass produced in millions and there are inevitably slight differences in color appearance and light output. Binning is way of sorting the chips so that all the LEDs from one particular bin look the same and have similar light output.

A light engine is the LED equivalent of a conventional lamp. It normally consists of a LED chip mounted on a circuit board that has electrical and mechanical fixings, meaning it is ready to be fixed in the luminaire. Note that the light engine may not consist of only one chip; it may be an array of 9 or 16, sometimes with a phosphor coating.

LEDs have no gases, filaments and no moving parts to fatigue. They provide light through a one-step process that takes place within the diode. There is no glass to break or screwed contacts to loosen.

LEDs are made of electronic components that need to be packaged together to offer long lasting efficient light sources to the end user. Apart from the LED chip itself which has sapphire and gallium in the semiconductor, the process of packaging with materials like ceramic, rare earth phosphors, silicone, solder and gold wire add to the overall cost. White LEDs require further tests for calibration and standardization.

LEDs are made of electronic components that need to be packaged together to offer long lasting efficient light sources to the end user. Apart from the LED chip itself which has sapphire and gallium in the semiconductor, the process of packaging with materials like ceramic, rare earth phosphors, silicone, solder and gold wire add to the overall cost. White LEDs require further tests for calibration and standardization.

Although the initial cost of conventional light sources is less than LEDs, the operational and maintenance costs of LED are significantly lower. LEDs, having a longer life, reduce maintenance and lamp replacement cost. . Because LEDs need to be replaced less frequently, the owner spends less on new lamps and the labor needed to change them. LEDs also consume less energy; thus the overall cost of a LED system can be significantly lower than that of conventional lighting systems. Most applications with LEDs offer a payback period as low as three to four years.

Although the initial cost of conventional light sources is less than LEDs, the operational and maintenance costs of LED are significantly lower. LEDs, having a longer life, reduce maintenance and lamp replacement cost. . Because LEDs need to be replaced less frequently, the owner spends less on new lamps and the labor needed to change them. LEDs also consume less energy; thus the overall cost of a LED system can be significantly lower than that of conventional lighting systems. Most applications with LEDs offer a payback period as low as three to four years.

Some of the strategies for reducing the cost of LEDs in the future are:

• Reduction in the production process.
• Simplification and reduction in the number of components.
• Introduction of new materials.