How LEDs Work

LIGHT EMITTING DIODES (LEDs)

LED technology has been around since the 1960s and has long been used in the displays of digital clocks and watches, in remote controls to generate infrared (IR) signals and as the green/red indicator light on appliances. Scientific advances since the early 2000s have allowed for use in an increasing number of devices and settings; for example public signage and traffic lights, display backlighting in mobile phones and high-definition televisions and to replace traditional forms of lighting.

LEDs are lighting devices that are solid-state, meaning that electricity flows through a solid material. The diode in an LED is what radiates light and is simple semiconductor; materials with different abilities for electrical conductivity are known as semiconductors. Semiconductors only partially conduct electricity and impurities (different materials) are often added to increase conductivity.

A diode is composed of two layers, an electron-rich (rich) layer and an electron-attracting (poor) layer. The rich layer has extra electrons that will move toward areas with positive charge. Impurities in the poor layer create ‘holes’ that allow electrons to travel through. When electricity is applied with the positive charge connected to the poor layer, a circuit is formed. Electrons flow from the rich layer to the poor layer and as electrons drop into the holes they lose energy. This energy is released as light.

The key advantages of LEDs are their efficiency, lifetime and durability. They emit more light per watt than incandescent, fluorescent (including compact fluorescent), halogen and High-intensity Discharge (HID) lights. LED lights have a useful lifetime that exceeds existing forms of lighting; our LED lights are rated for 50,000 hours of use. LEDs also resist damage from turning on/off and physical shock because they are solid-state components.