LEDs (Light Emitting Diodes) are rapidly replacing incandescent light bulbs in a variety of high reliability applications, including traffic lights, brake lights, emergency exit signs and more recently residential and commercial lighting.
The first LEDs were introduced in the 60's which only came in red. In the 70's, amber and green were introduced, along with intermediate colours such as orange. However, back then the materials used were inefficient. Over the years, LED efficiency, brightness, and lowered costs have exploded in parallel with computer components. Today, LED power efficiency surpasses that of fluorescents and compact fluorescents and is increasing with up to 90% efficiency, in contrast to the 6% efficiency of a standard incandescent. LEDs have also evolved to last much longer.
LED lighting is truly the most advanced, sophisticated and the most practical lighting technology that is available today.
LEDs are constructed from tiny solid-state chips (Diode's). These chips directly convert electricity to light without the use of a filament or glass bulb. Instead, the chips are encapsulated in solid plastic that can be made into a variety of shapes and sizes. Since LEDs have no filament, there is nothing to burn out and no need for a breakable bulb. Without the burning filament, very little heat is produced.
Today, LED lifetimes are not specified by a time to burnout because it simply takes too long to measure. Instead, LED lifetime is specified at time when a barely noticeable loss of light occurs. This lifetime is about 80,000 hours, or more than eleven years of time. If the LED is off for any portion of time, then this lifetime increases. Conventional light bulbs are typically rated at about 1000-2000 hours or so before they burn out, however this rating assumes that the light bulbs are not turned off and on, and that they are not jarred in any fashion.