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red LED
A red LED keylight
Essential Equipment
Light Improvements
    In our last issue I recounted my adventure in Joshua Tree National Park with my daughter, Lib. After night fell and we were still lost we relied on a small flashlight to help us find the trail.

conventional flashlight
My conventional pack flashlight

    The flashlight was one of those nice little metal ones that uses two AA-size cells and a bright krypton lamp, a pretty good performer for short-duration use, but without enough power for longer periods. Actually, these small, standard flashlights have a few unusual problems. First, their brightness comes at a cost—fairly high current drain. Maximum useful life for a pair of batteries is in the neighborhood of a continuous hour, maybe two.
    A subtle problem is the krypton lamp. It's very bright, but it's also very fragile. Drop the light while it's on and the hot lamp filament will probably break from the shock. The automotive industry encountered the same problem with tail lamps installed in rear trunk covers. Slam the trunk with the lights on; break the lamp filaments.

New Sources
    Over the last several years, quietly, a minor revolution in light sources has been in progress. The goal is to improve lamp efficiency: increase lamp output, reduce current consumption, and reduce lamp heat and fragility.
    When I worked in audiovisual all projectors used incandescent lamps. They were expensive, short lived, and limited in brightness, and sometimes they did strange things when they blew out. When I left AV for TV production a new projector light source was beginning to be used, the low voltage arc lamp. Current consumption was about the same as older lamps, heat production was about the same, life was longer, but, most important, brightness was many times greater. The hitch? They were very expensive and available in only a few top-of-the-line projectors.
    About the same time, solid-state engineers were beginning to design and produce high brightness LEDs (light emitting diodes). At first they were available only in red, but they were about ten times brighter than the older LEDs being used as indicators, and they drew about the same current. One or two novelty manufacturers produced tiny LED keychain flashlights, but a red flashlight isn't very useful for, say, reading a colored map.
(1)To put things in perspective, the small conventional krypton light Lib and I had used began to dim after only about an hour. The Brinkmann LED can operate continuously for four full days before dimming. If I were exploring a cave the LED flashlight would give me a superior safety margin.
    Then came high output LEDs in yellow, green, and at last, blue! Now we were getting somewhere.
    After my trip to Joshua Tree, I saw an innovative LED flashlight in a WalMart store. It boasted a white light, lamp life of hundreds of thousands of hours, and a battery life of more than a hundred hours! It used only two AA cells for power(1). I love new toys; I had to try it!

Brinkmann LED
The Brinkmann LED flashlight

    The lamp in the Brinkmann LED flashlight is actually a bi-color LED (yellow and blue on one substrate). The effect is of a cold white light that is really bright enough to be useful.(2)
(2)For me LEDs offer another small advantage. When my camera or flash batteries have dropped to a level too low to cycle the flash efficiently, they still have enough power to use in the LED flashlights. Am I cheap, or what?

But Things Get Better And Better
    The little Brinkmann had caught my attention. Were there others that might be more useful? I tried the internet and hit pay dirt in the form of a variety of LED headlamps. I bought two, one that is all LED (three LED lamps, three brightness levels plus two signal flashers, running on two AAA cells for about 160 hours) and one that is a hybrid: LED and krypton lamp, selectable, with a very sturdy three-strap headband. Again, two AAA cells and very long battery life in the LED mode. Since Then I've found the same lights in sporting goods stores for about the same price as online.
    At another site I found high brightness white keychain LED lights for less than $3.00. These are very bright and very small; great for stocking stuffers.
white LED
A bright white keylight
princeton headlamp
The Princeton headlamp
Hands-Free Light
    So what do you do with an LED headlamp? Well, explore the desert at night or enter dark caves. But a more mundane use I've found is working on appliances in dim rooms. I used my Princeton light (very light weight) when my air conditioner blower had to be replaced. The air handler closet was dark, and using the headlamp left both hands free to do the job.
    I've put LED headlamps in my pack and in my car. The older krypton units will be good for spares around the house, but, truthfully, they won't get much use—the LED lights are just too convenient. By buying alkaline AA and AAA cells in large packs, the prices are low, and that makes the system complete.
streamlight headlamp
The Streamlight hybrid headlamp

Further Improvements
    With the introduction of electronic projectors to the general market place, you can see the final (or current) result of projector lamp technology. New projectors ALL use low voltage arc lamps and brightness and contrast are superb. The units actually produce less heat than the older incandescent units. The replacement lamps are a bit pricey—about $150 to $350—but their life is long and the projectors have built-in resettable lamp clocks that indicate how many hours the lamps have been in use. Predicting and tracking arc lamp life is very simple.
    LED lamps and arc lamps are appearing everywhere. In our county all traffic light and crossing lamps have been replaced by LED matrices. They're very visible, and they should end the occasional requirement of blocking traffic to replace lamps. Many of our new school buses and industrial trucks have LED tail and brake lamps. No problem.
   In general, the future of these new technologies looks very bright (pun intended).

Where to Obtain LED Flashlights
    By now, LED flashlights and headlamps are easy to obtain in local stores. Try, first, WalMart's sporting goods department. I've also seen an excellent collection at The Academy sporting goods megastore. And try this online source, if you prefer to shop that way: www.brightguy.com. There are many others; use your search engine. Most of these online stores stock a variety of LED and conventional flashlights.
enjoy

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