Gadget Addict

Flashlights

It has been over a hundred years since the handheld flashlight was invented. Out of the creation of the incandescent light bulb was born the idea to create a device that would provide a mobile light source. There were obvious and endless uses for such a device if one could be made in a practical way.

The problem was finding an adequate way to power such a device. Batteries existed but they were cumbersome and their liquid electrolytes were prone to spilling and leakage. The solution came in the 1890's when the first dry cell batteries were introduced. These batteries used a paste electrolyte that was durable, did not spill, and could function in any orientation.

Soon after, an English inventor named David Misell patented a device that held two of these dry cell batteries in series within a heavy paper tube capped on one end with a small incandescent bulb mounted above a brass reflector ring. This was the first flashlight. The word flashlight comes from the inability of these early devices to provide a steady light due to the function of the primitive zinc-carbon batteries which needed to 'rest' in between periods of use, hence the term flashlight. Although useful, these early flashlights were not practical enough for everyday use. That changed in the early 1920's with advances in battery technology and the use of the more efficient tungsten filament bulb. With increased efficiency and batteries that could provide a constant light, the use of the handheld flashlight increased dramatically.

Even with constant improvements in efficiency and countless refinements the basic design of the flashlight changed very little over the next seventy years. It basically consisted of a set of batteries, a switch, and an incandescent light bulb. It wasn't until the 1990's that the flashlight would undergo a significant change; the introduction of the LED or Light Emitting Diode. Standard flashlight technology employs an incandescent bulb which creates light by heating a suspended thin filament until it glows. This creates a great deal of heat while producing a yellow light. The inefficiency of this process requires heavy battery use and the suspended filament is fragile and prone to breaking. Additionally the standard flashlights light output decreases as the batteries are drained reducing effectiveness over the life cycle of the cells.

The Light Emitting Diode (LED) on the other hand uses a charged semi-conductor material wrapped in a clear solid resin to create light. The light is created when an electrical current changes the state of the material by an exchange of electrons. This process requires less energy and its greater efficiency results in a light that is much brighter than a standard flashlight. The solid resin covering of the LED also serves to protect it and this shockproof design vastly increases its durability over incandescent bulbs with their fragile filaments.

This renaissance in LED flashlight technology has greatly improved the performance and efficiency of an indispensable tool as it begins a new century.

Have the facts before you make a buying decision. For more information and a comparison of standard , go to http://www.squidoo.com/led-vs-standard-flashlight

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