Carroll County Times Articles
Technology Everywhere – Even in Lighting
by Ron Harrington – January 15, 2006
When you turn out your lights to turn in for the night take a look around. There is no doubt you will notice beams of red, green and even blue lights coming for sources other than those resulting from flipping a switch or turning a knob. Perhaps you see blue coming from your refrigerator door, or green from you cell phone. There's the red light on the electrical outlet and maybe even on your toaster. These indicators lights can be found in virtually every electronic device known to man. They use a relatively unfamiliar light emitting electronic chip that has the potential for revolutionizing the concept of lighting and for bringing with it significant ecological and economic benefit to society.
We've Come a Long Way In Lighting
Until the dawning of the industrial revolution the sun and fire were the only sources of illumination. The torch, the candle, the lantern and the gas light are all examples of technological break-throughs in lighting by fire. With electricity came the incandescent light bulb which replaced fire as the source of light. Incandescent lighting produced ample quantities of light, lent itself to mass production, and became widely accepted for use in general lighting for both illumination and indication. Today, incandescent lamps are still being used in homes, restaurants and spaces that rely on the warmth and ambiance afforded by the reddish-white color given off by incandescent light.
Fluorescent Tubes and High-Intensity Arc Lamps
The mid-twentieth century brought with it fluorescent tubes and high-intensity arc lamps which used electrified gasses to produce bright white light. In spite of greater efficiency, their bluish and yellowish overtones resulted in poor color rendering. Consequently, the application of these light sources has been limited to spaces where illumination costs rather than light quality were of primary concern, such as in indoor office spaces and in outdoor parking lots.
Light Emitting Diode (LED)
With the age of electronics came the electronic chip known as the light emitting diode, or LED, which has traditionally been used in light indicator applications. LED's have many advantages over incandescent bulbs: they consume very little power, convert nearly 100% of the applied energy into light, give off little or no heat, and have extremely concentrated internal brightness. Since LED's also have a useful life of over 50,000 hours, more than twenty incandescent lamp changes would be needed to equal the life span of a single LED - a compelling reason to make the conversion from incandescent bulbs to LED's. LED's have already replaced light bulbs in virtually all indicator applications, and now with the advent of super bright LED's, many illumination applications are being taken over by LED's as well.
LED's are being seen in increasing numbers on the highway in traffic signals and in tail lights on cars, trucks, tractor-trailers and buses. They are cropping up in spotlights for retail display and stage lighting applications. Recently, a prominent auto manufacturer has for the first time used LED's for high beam headlights. In each headlight are nineteen light emitting diodes grouped around the center.
LED's characteristics hold the potential for a revolutionary reduction in energy consumption, which will happen once useful light output levels are realized. When wide acceptance is achieved and they become mass produced, consequential ecological and economic rewards will follow. Among the expected benefits of LED technology is improved air quality resulting from reduced fossil fuel consumption, fewer noxious gasses introduced into the atmosphere, curtailment of ozone layer depletion, reduced dependence on crude oil, lower illumination costs and more. The future, indeed, looks bright! Stay tuned.
About the Author
Ron Harrington is the owner of Protectron Lighting Control, and President of the Carroll Technology Council a non-profit organization dedicated to educating businesses, government and residents about technology issues. Questions are welcomed and may be addressed in future articles. Email advisors@carrolltechcouncil.org or go to www.carrolltechcouncil.org for a list of Advisor categories.
