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A headlamp, headlight, or head torch (UK) is a light source affixed to the head typically for outdoor activities at night or in dark conditions such as caving, orienteering, hiking, skiing, backpacking, camping, mountaineering or mountain biking. Headlamps may also be used in adventure races. Headlamps are often used by workers in underground mining (the head-mounted forms of mining lamps), search and rescue, surgeons, and by other workers who need hands-free directed lighting.
Headlamps are usually powered by three or four AA or AAA batteries, or rechargeable batteries. Systems with heavier batteries (4xAA or more) are usually designed so that the light emitter is positioned near the front of the head, with the battery compartment at the rear of the head.[ citation needed ] The headlamp is strapped to the head or helmet with an elasticized strap. [1] Some headlamps have a separate battery pack connected by a cable, to be carried on a belt or in a pocket. [1]
Headlamps may be held in place by a single band around the head or (particularly heavier ones) have an additional band over the top of the head.[ citation needed ]
Incandescent bulbs were used in headlamps until the introduction of white LEDs of sufficient brightness, with much lower power consumption and lifespan. [2] Power LEDs rated at 1 watt or more displaced incandescent bulbs in many models of headlamps. To avoid damage to electronic parts, a heatsink is usually required for headlamps that use LEDs that dissipate more than 1W. To regulate power fed to the LEDs, DC-DC converters are often used, sometimes controlled by microprocessors. This allows the LED(s) to maintain constant brightness until battery voltage becomes too low to operate the lamp, and allows selectable brightness. Following the introduction of LEDs for headlamps, sometimes combinations of LED and halogen lamps were used, allowing the user to select between the types for various tasks. [1]
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Carbide lamps were developed around 1900, and continued to be used after the introduction of battery lamps, which initially had poor battery life. Battery-powered headlamps with incandescent bulbs were used until the advent of LED lamps with much higher efficiency and consequently longer battery life.
Thomas Edison developed electric cap lamps for miners in 1914; by 1915, certain cap lamps were approved by the United States Bureau of Mines for safe use where there may be inflammable gas as in coal mines.[ citation needed ] These included features such as spring-loaded contacts to automatically disconnect broken bulbs. [3] These lamps consisted of an incandescent lamp with a reflector, and a belt-mounted wet-cell storage battery[ citation needed ] sized to power the lamp for the entire working shift.[ citation needed ] After 12 hours a 1917-era miner's lamp produced less than one candlepower and about 2 to 5 total lumens. [3] This pattern became popular for similar lamps. [4] Head lamps approved for use in coal mines are designed not to allow an internal spark to ignite flammable gas surrounding the headlamp.[ citation needed ]
While a head torch has the function of fitting on a person's head, being capable of being switched on and off, and illumination in front, there are many variations for different purposes. [5] They include:
An electric light, lamp, or light bulb is an electrical component that produces light. It is the most common form of artificial lighting. Lamps usually have a base made of ceramic, metal, glass, or plastic which secures the lamp in the socket of a light fixture, which is often called a "lamp" as well. The electrical connection to the socket may be made with a screw-thread base, two metal pins, two metal caps or a bayonet mount.
Lighting or illumination is the deliberate use of light to achieve practical or aesthetic effects. Lighting includes the use of both artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylight. Daylighting is sometimes used as the main source of light during daytime in buildings. This can save energy in place of using artificial lighting, which represents a major component of energy consumption in buildings. Proper lighting can enhance task performance, improve the appearance of an area, or have positive psychological effects on occupants.
A flashlight or electric torch, usually shortened to torch, is a portable hand-held electric lamp. Formerly, the light source typically was a miniature incandescent light bulb, but these have been displaced by light-emitting diodes (LEDs) since the early 2000s. A typical flashlight consists of the light source mounted in a reflector, a transparent cover to protect the light source and reflector, a battery, and a switch, all enclosed in a case.
A headlamp is a lamp attached to the front of a vehicle to illuminate the road ahead. Headlamps are also often called headlights, but in the most precise usage, headlamp is the term for the device itself and headlight is the term for the beam of light produced and distributed by the device.
Photometry is a branch of optics that deals with the measurement of light in terms of its perceived brightness to the human eye. It is concerned with quantifying the amount of light that is emitted, transmitted, or received by an object or a system.
Maglite is a brand of flashlight manufactured in the United States by Mag Instrument, Inc. located in Ontario, California, and founded by Anthony Maglica. It was introduced in 1979. Constructed principally of anodized 6061 aluminum, they have a variable-focus beam. Maglites are produced in several colors such as black, silver, blue, red, green, purple, gold, and different finishes. Originally Maglite flashlights used krypton or xenon incandescent bulbs. Current models have LEDs, although the older models are still widely available.
Bicycle lighting is illumination attached to bicycles whose purpose above all is, along with reflectors, to improve the visibility of the bicycle and its rider to other road users under circumstances of poor ambient illumination. A secondary purpose is to illuminate reflective materials such as cat's eyes and traffic signs. A third purpose may be to illuminate the roadway so that the rider can see the way ahead. Serving the latter purposes require much more luminous flux and thus more power.
A compact fluorescent lamp (CFL), also called compact fluorescent light, energy-saving light and compact fluorescent tube, is a fluorescent lamp designed to replace an incandescent light bulb; some types fit into light fixtures designed for incandescent bulbs. The lamps use a tube that is curved or folded to fit into the space of an incandescent bulb, and a compact electronic ballast in the base of the lamp.
A tactical light or weapon light is a flashlight used in conjunction with a firearm to aid low-light target identification, allowing the user to simultaneously aim a weapon and illuminate the target. Tactical lights can be handheld or mounted to the weapon with the light beam parallel to the bore. Tactical lights can also serve as a non-lethal weapon, used to temporarily blind and disorient targets or, in the case of a large handheld flashlight, to be used as a blunt weapon.
An emergency light is a battery-backed lighting device that switches on automatically when a building experiences a power outage.
A Carbide lamp or acetylene gas lamp is a simple lamp that produces and burns acetylene (C2H2), which is created by the reaction of calcium carbide (CaC2) with water (H2O).
A mechanically powered flashlight is a flashlight that is powered by electricity generated by the muscle power of the user, so it does not need replacement of batteries, or recharging from an electrical source. There are several types which use different operating mechanisms. They use different motions to generate the required power; such as squeezing a handle, winding a crank, or shaking the flashlight itself. These flashlights can also be distinguished by the technique used to store the energy: a spring, a flywheel, a battery or a capacitor.
Gas-discharge lamps are a family of artificial light sources that generate light by sending an electric discharge through an ionized gas, a plasma.
A light fixture, light fitting, or luminaire is an electrical lighting device containing one or more light sources, such as lamps, and all the accessory components required for its operation to provide illumination to the environment. All light fixtures have a fixture body and one or more lamps. The lamps may be in sockets for easy replacement—or, in the case of some LED fixtures, hard-wired in place.
Eveready Industries India Ltd. (EIIL) is an Indian company that manufactures and markets batteries and lighting products. The Eveready brand has been present in India since 1905. It also manufactures photogravure plates, castings, carbon electrodes and related products.
An LED lamp or LED light is an electric light that produces light using light-emitting diodes (LEDs). LED lamps are significantly more energy-efficient than equivalent incandescent lamps and fluorescent lamps. The most efficient commercially available LED lamps have efficiencies exceeding 200 lumens per watt (lm/W) and convert more than half the input power into light. Commercial LED lamps have a lifespan several times longer than both incandescent and fluorescent lamps.
Holiday lighting technology has been subject to considerable development and variation since the replacement of candles by electric lights. While originally used during the Christmas holidays as Christmas lights, modern electric light arrays have become popular around the world in many cultures and are used both during religious festivals and for other purposes unconnected to any festivities.
A trouble light, also known as a rough service light, drop light, or inspection lamp, is a special lamp used to illuminate obscure places and able to handle moderate abuse. The light bulb is housed in a protective cage and a handle that are molded to form a single unit. It has a long power line for distant reaching; the handle may also have an electrical outlet on it, allowing the light to also double as an extension cord.
Solar powered flashlights or solar powered torches are flashlights powered by solar energy stored in rechargeable batteries. Most of these flashlights use light-emitting diodes lamps since they have lower energy consumption compared to incandescent light bulbs.
A dive light is a light source carried by an underwater diver to illuminate the underwater environment. Scuba divers generally carry self-contained lights, but surface supplied divers may carry lights powered by cable supply.