Flashlights became very popular in China by the end of the 1930s, 60 companies made flashlights, some selling for as little as one-third the cost of equivalent imported models. In 1922 there were an estimated 10 million flashlight users in the United States, with annual sales of renewal batteries and flashlights at $20 million, comparable to sales of many line-operated electrical appliances. By 1922 several types were available the tubular hand-held variety, a lantern style that could be set down for extended use, pocket-size lamps for close work, and large reflector searchlight-type lamps for lighting distant objects. The advantage of instant control, and the absence of flame, meant that hand-held electric lights began to replace combustion-based lamps such as the hurricane lantern. Development of the tungsten-filament lamp in 1904, with three times the efficacy of carbon filament types, and improved batteries, made flashlights more useful and popular. The company donated some of these devices to the New York City police, who responded favorably to them.Ĭarbon-filament bulbs and fairly crude dry cells made early flashlights an expensive novelty, with low sales and low manufacturer interest. 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. 617,592, assigned to American Electrical Novelty and Manufacturing Company. On January 10, 1899, British inventor David Misell obtained U.S. It could be instantly turned on and off, and avoided fire risk. The electric lamp was odorless, smokeless, and emitted less heat than combustion-powered lighting. Portable hand-held electric lights offered advantages in convenience and safety over (combustion) torches, candles and lanterns. The first mass-produced dry cell batteries came in 1896, and the invention of portable electric lights soon followed. This was the first battery suitable for portable electrical devices, as it did not spill or break easily and worked in any orientation. Unlike previous batteries, it used a paste electrolyte instead of a liquid. The first dry cell battery was invented in 1887. January 1899 Ever-Ready flashlight ad mentioning the proceedings against the alleged patent-infringing rival companies. Consequently, they could be used only in brief flashes, hence the common North American name "flashlight". Because these early flashlights also used energy-inefficient carbon-filament bulbs, "resting" occurred at short intervals. Some flashlights can be used under water or in flammable atmospheres.Įarly flashlights ran on zinc–carbon batteries, which could not provide a steady electric current and required periodic "rest" to continue functioning. Head- or helmet-mounted flashlights designed for miners and campers leave both hands free. In addition to the general-purpose, hand-held flashlight, many forms have been adapted for special uses. Flashlights are used as a light source outdoors, in places without permanently installed lighting, during power outages, or when a portable light source is needed. Some have solar panels to recharge the battery. Some are powered by the user turning a crank, shaking the lamp, or squeezing it. Today, flashlights use mostly light-emitting diodes and run on disposable or rechargeable batteries. The invention of the dry cell and miniature incandescent electric lamps made the first battery-powered flashlights possible around 1899. A typical flashlight consists of the light source mounted in a reflector, a transparent cover (sometimes combined with a lens) to protect the light source and reflector, a battery, and a switch, all enclosed in a case. Formerly, the light source typically was a miniature incandescent light bulb, but these have been displaced by light-emitting diodes (LEDs) since the mid-2000s. For other uses, see Flashlight (disambiguation).Ī set of LED flashlights The angle-head flashlight (Fulton MX-991U) on the left uses an incandescent bulb, while the adjustable angle-head flashlight (Streamlight Sidewinder) on the right uses LEDs to give white, red, blue, and infrared lightĪ flashlight ( US, CA) or torch ( UK, AU) is a portable hand-held electric lamp.
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