Published on July 8th, 2011 | by Aaron Fown1
Quantum Tunneling Composites Lead to a More Efficient Flashlight, And More!
July 8th, 2011 by Aaron Fown
Torches as a Leapfrogging Technology
Most of us have grown up in an environment where power comes from a plug in the wall, and lights are fixtures or lamps that take advantage of that system. But in many parts of the world, this infrastructure doesn’t exist, and so people spend a lot of money on dirty, smelly Kerosene to light their houses at night. Something so simple as a bright, dependable LED flashlight can be an excellent leapfrogging technology for people in such places, as it can provide clean, safe light that can be ‘filled up’ with a tiny solar battery charger. And even in western countries, a bright LED torch burning at just a few watts can often fill a room with light, if you are really dedicated to power savings.
But, as LED’s have gone from being bright to really, really bright, a problem has arisen. For most uses, the true power of modern LED’s is . . too much. You can’t read or cook with 300 lumens of light; that much light is really only useful for searching the woods, or for lighting an entire room by pointing the torch up at the ceiling. And if you don’t need all of that light, why waste electrons producing it? LED’s work more efficiently if they are under-driven anyway.
Many hobbyists and manufacturers have risen to this challenge by producing complex, and in many cases highly refined, torches that use resistors, or pulse width modulation via a tiny computer chip, to cut the light level and save power. However, such systems have far more parts and much higher complexity than lights which are simply regulated, which adds to the cost of the torch and increases the risk of failure. Also, such circuits always have some overhead that cuts into the efficiency of the light.
Now, an American company has a new solution to the brightness problem, one that cuts the complexity, increases the efficiency, and does it all with a simple and cheap material.
Peak LED Solutions
The company is Peak LED Solutions, one of the early innovators in the LED flashlight field. They were amongst the first to build super-tough LED lights, using metals like brass and steel, for use in demanding environments. They also have some of the most efficient energy regulation circuitry in the industry, and have built their reputation on lights that are tiny, modular, bright, and virtually indestructible. As a result, Peak flashlights have a strong following amongst adventurers and the military who need torches that will work no matter how harsh the environment.
But, in recent years, they have lost some business to other manufacturers that had lights capable of putting out multiple levels, because they were dedicated to toughness, and no multi-level system could withstand the extreme levels of abuse that they expect their torches to endure. But now they have a new solution that uses no circuity at all, wastes no electricity, and is super tough — a quantum tunneling composite.
Quantum Tunneling Composite
In 1997, David Lussey, an electrical engineer in the UK, was working on developing an adhesive for a security system. The project called for a conductive adhesive to complete a circuit, so that if the circuit was broken, the alarm would sound. His experiments came up with something completely different, however, as is often the case in science.
The material he came up with is a perfect insulator… until it is compressed. When compressed, the polymer would gradually become a better and better conductor, until, under high pressure, it eventually became an almost perfect conductor. This effect is caused by the tiny particles of nickel in the polymer — as the material is compressed, the particles are pressed closer together. They never touch, but once they cross a critical threshold electrons begin to jump (technically, teleport) between the particles of nickel, in a process called quantum tunneling. Thus the name.
Lussey has continued his research into the material with the company that he founded after his discovery, Peratech. However, the material was too fragile for use in a torch without some clever engineering. Although it is highly resistant to compression, it’s weak to shear and lateral forces, so the material would break down quickly if you just put it in the bottom of the flashlight tube. The engineers at Peak solved this problem by encapsulating the QTC material in a brass pill. This solution greatly lengthens the life of the QTC polymer, and also allows for easily swapping out the pill should it wear out.
For now, the QTC technology is only being used in Peak torches (which can only be purchased through their authorized distributor, or by calling them). Peak flashlights are really nice, but they are out of the price range of the people who need LED light the most. But this technology is simple and cheap enough that it could easily spread into other, more appropriate lighting projects, like the BoGo Light or the Nokero Solar Bulb. In fact, the QTC material could be used for voltage regulation in any application where a conventional potentiometer or regulator might be used, such as in small electric fans or pumps. Hopefully, people throughout the world will soon be able enjoy tough, sustainable LED lights that are bright or dim, depending upon their needs, and the applications of this material will only grow with time.
You can watch a demonstration of a QTC Peak light in action here.
Photo credit: Peak LED Solutions
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