The Future's So Bright

A flashlight made from high-output LEDs is not for the fainthearted

2 min read

Anyone who thinks that LED illumination is for wimps should look at—not into—one of Wayne Johnson’s new flashlights. With 4 four-chip LED modules, it puts out roughly the same light as a 200-watt incandescent bulb. Parabolic reflectors point most of that light into a beam that can illuminate the landscape dozens of meters away.

Johnson, a former computer programmer, reports that he first got into custom flashlights because he liked to take nighttime walks. But confrontations with furiously barking dogs he couldn’t even see or skunks he could make out only when well within spraying range made his evening ambles more chancy than he liked. Incandescent flashlights had too little battery life, and LED units cast a negligible beam. When the first 1-watt LED modules appeared, he was hooked. For more than five years he’s supported himself with Elektro Lumens, a company that makes both high-output LED conversion kits for conventional flashlights and whole custom-built models for the deep pocketed.

Johnson’s newest flashlight, the FireSword-IV, looks a little like an art deco Olympic torch: The body is turned from a solid piece of aluminum, with fine cutting-tool marks that provide a nonslip grip. The head is turned from a larger-diameter chunk, with deeply incised fins that dissipate the heat thrown off by both the LEDs and the batteries, which are special lithium-ion rechargeables with relatively low internal resistance. The flashlight weighs just under a kilogram with batteries, and it casts a beam that’s bright even in daylight.

The roughly 9.5-watt modules that give the flashlight its power come from Cree, in Durham, N.C., one of several companies competing in the high-intensity LED market. Though residential fixtures are also available for renovations and new construction, for the most part today’s superbright LED lights go to commercial and institutional customers, for which the high cost of a single module—and the need to revamp existing lighting fixtures—is less important than LEDs’ energy savings and fantastically long life.

Going out with a FireSword-IV at night is an experience that’s not easy to describe. Streetlights and car headlights cast relatively wan beams in comparison. The only drawback to that much light right in your hand is that nearby objects may be so brightly illuminated that anything past 20 meters or so starts looking pretty dark.

There’s another, subtler drawback that doesn’t strike you until you’ve been using the light for 15 or 20 minutes: Some of those watts coursing through the LEDs are bathing your surroundings in visible photons, but plenty of them are still turning into heat. Even with those cooling fins, the head of the flashlight and the forward sections of the handle become increasingly warm to the touch. If you stroll long enough, a FireSword-IV could well become too hot to handle.

Nevertheless, the device is a triumph of lighting machismo and amply makes the point that LED illumination can, under certain conditions, vanquish incandescent or fluorescent lights [see “The LED’s Darkest Secret,” elsewhere in this issue]. And for someone who regularly needs enormous light output in a tiny, cordless package, slightly dimmer Maglite replacement heads are available that might end up costing about the same as less outré rechargeable work lights.

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