High-Tech Flashlight Technology

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High-Tech Flashlight Technology

High-tech Flashlight Terminology

So you just finished reading our high-tech flashlight roundup and you’re wondering how the heck any flashlight could command a price tag north of $500. We produced this guide to help you understand the technology introduced in that story.

Color temperature: Outdoors, the ancient incandescent bulb that haven’t changed much since the days of Edison, still offer an advantage because they throw off very warm light that appeal to our eyes without the color shifts that can distract you. LED lights that are very cold or blue, can shift the color of plants enough to bother you. To address that, newer LED are often sold in color tints for those who plan to use the light outdoors and want the LED to emulate an incandescent more. These are often referred to as warm white or neutral white.

HID (High Intensity Discharge): Once seen as the holy grail of high-performance flashlights, this technology’s power consumption has most industry observers predicting that it will be eclipsed by high-performance LED technology. HID is similar to incandescent lamps in that it uses a bulb filled with an exotic gas. But instead of current being passed through a filament that heats up, two electrodes are used. The current is passed between these two electrodes creating an arc to produce light. HID’s produce an immense amount of light, but they also consume a tremendous amount of power. They’re also slow to start and can take as long as 30 seconds to reach full their brightness. That’s not a problem for applications such as automobile headlights, but a flashlight might be cycled on for only a few seconds at a time. HIDs aren’t very flexible when it comes to producing light at different levels and sizes, either.
 
Incandescent: This technology hasn’t changed much in 200 years. Copious amounts of electricity are pumped through a wire filament inside a vacuum-evacuated bulb until the wire glows white hot. The output can be tweaked by adding various gasses, such as halogen or xenon. Incandescent bulbs seem ancient, but they still have one advantage: they emit the full spectrum of light from ultra-violet to infrared. Although human vision cannot see in this range, we are still used to seeing the full spectrum of light. Most LEDs, by contrast, emit light along a very narrow spectrum, which can be problematic. Outdoor vegetation illuminated by an LED won’t appear to have the same colors that it will when illuminated by an incandescent light, for instance. An LED can overcome this buy putting out more lumens than an otherwise equivalent incandescent. The bad news for incandescents is that LEDs seem to have the extra output to spare, thanks to Moore’s Law.

LED (Light-Emitting Diode): LEDs produce light by running current through a semiconductor. The technology has been around for decades, but it’s appeared in flashlights only in the last six or seven years. Once dismissed as useful only for those tiny keychain lights, LEDs now outperform most incandescents and deliver far longer run times to boot. Most LED flashlights use single-die emitters, but some designs now feature multiple emitters on one package. Quad-die LEDs are common, and six-die models are also available. Heat is LED technology’s primary weakness. Electronics don’t like heat, and overheating an LED can kill it. Manufacturers address this by adding adding beefy heat sinking to keep it cool and thermal regulation to throttles the chip back if still overheats. LEDs are essentially the whole ball game when it comes to flashlights today. When you consider output, power consumption and durability (there’s no filament to break or bulb to shatter), LEDs can’t be beat.

Li-ion (Lithium Ion): The Li-ion cells that power phones, laptops and power tools are also popular for more advanced flashlights. Li-Ions offer high capacity, low weight, and generally very good performance in cold weather. For people close to chargers, a Li-ion option is often preferred. Many lights will run on Li-ion cells and also take standard disposable lithium cells for field use.

Lithium Primary: The most popular cell running high performance flashlights today is the lithium CR123. Originally developed to power small point-and-shoot film cameras, these small three-volt cells pack a lot of energy into a very small form factor. They also offer far better cold weather performance than an alkaline and maintain a charge after sitting on a shelf for a very long time. The main disadvantage is price. At retail, these photo batteries often fetch $6 a cell. Fortunately, they can be purchased online for as low as $1.25 a piece. Soldiers and others who rely on the flashlight in the field without access to a charger often prefer a lithium primary battery.

Lumens: Flashlight output used to be marketed in candlepower, but since that measurement is taken only at the brightest point of the beam, it doesn’t measure usable light that spills out the side. Today, most lights are evaluated and marketed based on their output in lumens, as measured by a device known as an integrated sphere that’s capable of measuring all the flashlight’s output.

NiMH (Nickel-metal Hydride): Nickel-metal hydride cells self-discharge fairly rapidly and aren’t as capable as Li-ion cells. Newer low-self discharge cells, such as Sanyo’s Eneloops, have helped address this shortcoming, and they’re a good substitute for the more common alkaline cells. High-performance flashlights designed to run on AA alkaline batteries often deliver their best performance while running NiMH cells, which can deliver higher discharge rates than alkaline cells.
Reflector Options: Some flashlights offer options to swap out their smooth reflectors with textured or “orange peel” finishes that can smooth out the beam profile. Smooth reflectors generally offer the best throw but can also put out uglier patterns than textured reflectors. For most purposes, a textured reflector is preferred.

Regulation: Regulation helps control a flashlight’s power consumption keeps its brightness levels flatter than non-regulated lights. Some lights offer better or tighter regulation than others, and some even combine methods where high-output modes are unregulated while low-output modes are. Very tight regulation is generally a good attribute, but not for every situation. It can deliver the same amount of light for the life of the battery, but then shut off abruptly to leave you literally in the dark. Lights that gradually decrease in brightness give you more advanced warning that you’re going to be stuck in that spooky haunted house without a light.

Spill: Don’t confuse spill with flood. Spill generally refers to how much useful light is spilled out the side of the beam. Some designs can be all throw with very little spill. This is fine if you need to light something up at 100 yards, but a laser-like beam isn’t very useful when you’re walking a trail and want to know where the edge of the cliff is at.

Throw: The throw on a flashlight is how far the beam will travel downrange. Manufacturers can use optics, reflectors, or total internal reflectors to tune a flashlight’s throw. If you’re likely to use your flashlight in your home or in close quarters, you might prefer a flashlight that produces more flood.

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DanFree

Light Done Right - Never Bring a Maglite to a real flashlight fight. - The title of your article.

It appears that you have something against Maglites. I am only a consumer and fan of Maglites which is a good American product at a good price.

So... the question is, what is a flashlight fight? If I were going to fight you with flashlights, I would probably beat the crap out of you with a "Maglite 6-Cell D" any day of the week. And for the price of the flashlights featured in your article, I could probably get at least 3, and depending upon which flashlight you choose, a lot more. That way I could also throw them at you before you got very close.

Also, it appears that you did not investigate the current Maglite product line-up. They have a rechargeable Maglite with accessories so you can even recharge from the cigarette lighter plug in your cars. The Magcharger - NiMH/Halogen puts out 221 Lumens according to their product specs. They also have a new line of LED flashlights and for several years, aftermarket vendors have been offering LED modification kets for some of their flashlights.

 

 

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