Flashlight

A flashlight sometimes called a torch is a hand-held electric-powered light source. Mostly the lightsource is a small incandescent lightbulb or LED (light-emitting diode). Most flashlight designs composed of a lightbulb or LED mounted in a funnel or parabolic shaped reflector, transparent glass or plastic glass to cover the light bulb from debris or damage, a power source such as battery, container and a power switch.

While most of the flashlights are hand-held, there are also head lamp or helmet-mounted flashlights designed for miners and camper and flashlights for bicycles. Other flashlights power by generators (hand-cranked generators) or electromagnetic induction or solar-charged capability.

The name Flashlights is used mainly in United States and Canada but in other English-speaking countries it’s called torch or electric torch.

History of Flashlight

In 1896, the first dry cell battery was invented. Unlike previous batteries, it used a paste electrolyte instead of a liquid. This was the first battery suitable for portable electrical devices, as it did not spill or break easily and worked in any orientation.

On January 10, 1899, American Electrical Novelty and Manufacturing Company obtained U.S. Patent No. 617,592 (filed 12 March 1898) from David Misell, its English inventor. This "electric device" designed by Misell was powered by "D" batteries laid front to back in a paper tube with the light bulb and a rough brass reflector at the end. The company donated some of these devices to the New York City police, who responded favorably to them.

These early flashlights ran on zinc–carbon batteries, which could not provide a steady electric current and required periodic 'rest' to continue functioning. Because these early flashlights also used energy-inefficient carbon-filament bulbs, "resting" occurred at short intervals. Consequently, they could be used only in brief flashes, hence the popular name flashlight.