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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