By Larry Houser, October 25, 2004
LEDs (light emitting diodes) are the next big thing in
an industry which is always looking for flexible and
cost effective technology. Now used frequently in
commercial spaces to backlight signs and displays, these
lamps (the lighting industry's term for "light bulbs")
have a proven track record of reliability. Originally
designed as indicator lights in the 1960's these lamps
have come a long way.
Luminaires (the lighting industry's term for "light
fixtures") that use LEDs are both flexible and highly
efficient, two traits that lighting designers prize over
all others. How would you like to significantly cut down
your lighting electrical bill? How about only having to
change lamps every 7 years? This ultra-long life light
source lasts 75,000 to 100,000 hours compared to 750 for
the typical incandescent household lamp.
The common incandescent lamp was invented in a time when
horse and buggy were still the primary mode of
transportation. It works by charging a thin piece of
metal with electricity to the point that it glows.
Unfortunately only about 10 percent of the energy
consumed goes toward creating actual light: the rest is
wasted as heat.
LEDs produce illumination completely differently. Built
on a semiconductor chip, one half of a diode is loaded
with electricity, which is then discharged across to the
other half of the diode. Light is created during this
energy release. The LED has a small reflector under the
diode so that almost all of the light created is bounced
forward through the epoxy shield that protects it.
These light sources are super compact, and since they
generate virtually no heat or sound, they can be placed
in areas that normal lamps could never go. These lights
are so flexible in fact, that Randall Whitehead,
internationally respected lighting designer and author
of seven books on lighting (including Residential
Lighting, A Practical Guide), thinks that "LEDs are going to
wipe fiber optics lighting techniques off the map". They
can be used in many of the same ways, but they don't
require anywhere near the same installation time or
service.
