LEDs Explained

LED stands for Light-Emitting Diode and is a semiconductor light source.  LEDs are used as indicator lamps in many devices, and are increasingly used for lighting.  An LED is a semi-conducting device that produces light when an electrical current flows through it.

Basically, LEDs are just tiny light bulbs that fit easily into an electrical circuit.  But unlike ordinary incandescent bulbs, they don't have a filament that will burn out, and they don't get especially hot.  They are illuminated solely by the movement of electrons in a semiconductor material. Introduced as a practical electronic component in 1962, early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet and infrared wavelengths, with very high brightness.

Energy-efficient lights consume 80 percent less energy than conventional, incandescent bulbs.  Common in digital clocks, remote controls, watches and appliances, they are now being produced in bulb form as a home lighting alternative.

Light-Emitting diodes; semiconductors that produce light when electricity passes through them.  LEDs are considerably more energy efficient than incandescent lights.

LED Advantages

LEDs have several advantages over conventional incandescent lamps.  For one thing, they don't have a filament that will burn out, so they last much longer.  Additionally, their small plastic bulb makes them a lot more durable.

But the main advantage is efficiency. In conventional incandescent bulbs, the light-production process involves generating a lot of heat (the filament must be warmed).  This is completely wasted energy, unless you are using the lamp as a heater, because a huge portion of the available electricity isn't going toward producing visible light.  LEDs generate very little heat, relatively speaking.  A much higher percentage of the electrical power is going directly to generating light  which cuts down on the electricity demands considerably.

LEDs are a more cost-effective lighting option for a wide range of situations.  While they may be more expensive than incandescent lights up front, their lower cost in the long run can make them a better buy.  In the future, they will play an even bigger role in the world of technology.

LEDs present many advantages over incandescent light sources including:

  • Lower energy consumption
  • Longer lifetime
  • Improved robustness
  • Greater durability and reliability


LED Characteristics

Efficiency: LEDs produce more light per watt than incandescent bulbs.  Their efficiency is not affected by shape and size, unlike fluorescent light bulbs or tubes.

Colour: LEDs can emit light of an intended colour without the use of the color filters that traditional lighting methods require.  This is more efficient and can lower initial costs.

On/Off time: LEDs light up very quickly.

Cool light: In contrast to most light sources, LEDs radiate very little heat in the form of Infra Red that can cause damage to sensitive objects or fabrics.  Wasted energy is dispersed as heat through the base of the LED.

Slow failure: LEDs mostly fail by dimming over time, rather than the abrupt burn-out of incandescent bulbs.

Lifetime: LEDs can have a relatively long useful life.  One report estimates 35,000 to 50,000 hours of useful life, though time to complete failure may be longer.  In comparison, fluorescent tubes typically are rated at about 10,000 to 15,000 hours, depending partly on the conditions of use, and incandescent light bulbs at 1,000 to 2,000 hours.

Shock resistance: LEDs, being solid state components, are difficult to damage with external shock, unlike fluorescent and incandescent bulbs which are fragile.

Focus: The solid package of the LED can be designed to focus its light.  Incandescent and fluorescent sources often require an external reflector to collect light and direct it in a usable manner.

Toxicity: LEDs do not contain mercury, unlike fluorescent lamps.