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Flashlight is a portable power tool which is a light source to illuminate and be operated with
battery. Usually the light source is from a small incandescent light or a fluorescent lamp known as the LED light. A typical flashlight design consists of a light source mounted in a parabolic reflector or other form, a transparent lens to protect the light source from damage, the energy source (ie the battery, and a
electric switch. The electric current from the battery to a small bulb at the front end which produces the light is controlled by a switch placed between the batteries and the lamp. Flashlights are generally used in dark places to illuminate something around them. Flashlight can be used by anyone in the event of a dead lamp, for a mechanic, a person who fixes electrical installations, workers in mining, and so forth. In the context of communication, a flashlight can be used to convey morse code in scout.
History
Before Flashlight Portable and practical light sources are constantly sought and developed throughout history. Torches and candles are the initial sources of light, which are then replaced by lanterns where people begin to learn how to burn various oils from animals or minerals. Until the 19th century, electricity was used or used to create light. The discovery of a flashlight may occur due to previous important discoveries, ie dry cell battery and
lamp . In 1898 the 'National Carbon Company' 'introduced its new invention of the first electric dry cell battery Unlike previous batteries, this type of battery uses a paste electrolyte instead of a liquid. This is a suitable first battery for portable electronic devices, because dry batteries will not spill or easily scatter. Earlier in 1879, Thomas Alva Edison invented the incandescent light bulb. Incandescent light bulbs are electric lights consisting of transparent or translucent glass coverings containing wire filaments (usually tungsten) that emit light when heated with electric power. These two discoveries support the discovery of the next flashlight. Flash Discovery
The first flashlight was introduced and widely traded in 1898 by a company owned by Conrad Hubert (whose real name is Akiba Horowits), after which it was named Eveready. Conrad Hubert saw the potential to develop this flashlight technology, so Hubert hired an English inventor, David Misell, who patented the invention of his portable electric light in 1895 and the lights on a bicycle in 1896 As an employee of Hubert, David Misell continued to find advances in lighting, and then patented his first flashlight discovery on January 10, 1899. This first flashlight was handmade consisting of raw paper and fiber tubes, with a light bulb and brass rough reflectors Misell and Hubert together assembled several tubular flashlights and gave them to some New York cops, and they got a good response from the policemen. Hubert then obtained a patent in 1905, for his invention of a flashlight with an on / off switch in a cylindrical package containing lights and batteries as they are now known The first commercial flashlight was exhibited in an electric exhibition held at Madison Square Garden, New York