| LEDs are rapidly replacing incandescent light bulbs in a variety of high reliability
applications, including traffic lights, brake lights, and emergency exit
signs. LEDs are constructed from tiny solid-state chips 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.
The first LEDs were introduced in 60's. These LEDs came only in red. In
the 70's, amber and green were introduced, along with intermediate colors
such as orange. However, back then the materials used were inefficient. Over
the years, LED efficiency, brightness, and lowered cost have exploded in
parallel with computer components. Today, LED power efficiency surpasses
that of fluorescents and compact fluorescents and is increasing, with 75%
efficiency on the horizon. Compare that to the 6% efficiency of a standard
incandescent.
Moreover, costs for a variety of colors have plummeted. Bright red,
amber, green and intermediate colors are very respectfully priced. Blue,
white, and purple were introduced in the 1990s completing a full palette of colors.
However, blue, white, and purple are more expensive.
LEDs have also evolved to last much longer. 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 100,000 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. But even this rating assumes that the
light bulbs are not turned off and on, and that they are not jarred in any
fashion.
Anyone familiar with holiday light strings is experienced with burnout.
LED Forever Bright(tm) lights are built with patent-pending circuitry to maximize
efficiency. This revolutionary design concept eliminates the use of
traditional components that add to cost and generate heat. In essence the
circuitry allows the LEDs to flash on and off with AC power. Like a
television set, the flashing occurs sixty times per second and is invisible
to the eye. By flashing the LEDs on and off this way, the circuit can be
made at least twice as efficient as is possible with traditional LED
circuitry. Therefore, the lifetime of these bulbs is rated at 200,000 hours
or more than 20 years of continuous use and much longer if just used
seasonally. |
