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Question 1

What are LEDs?

Answer

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.

Question 2

Why is LED technology classified as solid state lighting?

Answer

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 agaseous discharge medium to initiate production of light.

Question 3

What makes LEDs more robust than other light sources?

Answer

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.

Question 4

How is light produced in an LED?

Answer

Light emitting diodes produce light by the movement of electrons between the two terminals of diode, which occur by a process called electroluminescence. When a light emitting diode is electrically connected, electrons start moving at the junction of the N-type and P-type semiconductors within the diode. When there is a jump over of electrons at the p-n junction, the electron loses a portion of its energy. In regular diodes this energy loss is in the form of heat. However, in LEDs the specific type of N and P conductors produce photons (light) instead of heat. The amount of energy lost defines the color of light produced

Question 5

What does SMD mean?

Answer

SMD means surface mounted diode. This is a better technology than the first generation DIP LEDs. The SMD typeLEDs are mounted on an aluminum substrate and enveloped in an epoxy resin.

Question 6

What are the typical types of LED modules available in the market?

Answer

LED modules may be available in the following forms:
Prefabricated chip on board which can be used for specific applications by luminaire manufacturers who design the heat sink and mounting conditions. Chip on board with an optical lens or diffuser as a prefabricated piece with or without integrated heatsink. That can be used by luminaire manufacturers to integrate into luminaire. Retrofit lamps to replace older (halogen) technology. This comes with an integrated heat sink and standard lamp base that can fitted directly into existing luminaires with a standard lamp holder. Prefabricated luminaires with an integrated LED light source and heat sink complete with luminaire housing that is available as a sealed piece. The driver may be integral in the housing or may be remote.