Headlamp (outdoor)

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This article is about headlamps for outdoor activities. For other types of headlamps and headlights, see Headlight (disambiguation).
Black Diamond Spot attached to a helmet

A headlamp (known as a headtorch in the UK) is a light source affixed to the head 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, search and rescue, surgeons, and by other workers who need hands-free lighting.

Description[edit]

Headlamps are usually powered by three or four AA or AAA batteries.[citation needed] Systems with heavy 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] It is sometimes possible to completely disconnect a headlamp's battery pack, for storage on a belt or in a pocket.[1]

Lighter headlamp systems are strapped to the user's head by a single band; heavier ones utilize an additional band over the top of the user's head.[citation needed]

White LEDs were quickly adopted for use in headlamps due to their smaller size, lower power consumption and improved durability compared with incandescent bulbs.[citation needed] Power LEDs rated 1 watt or more have displaced incandescent bulbs in many models of headlamps.[citation needed] To avoid damage to electronic parts, a heatsink is usually required for headlamps that use LEDs that dissipate more than 1W.[citation needed] To regulate power fed to the LEDs, DC-DC converters are often used in 1W+ lights, sometimes controlled by microprocessors.[citation needed] This allows the LED(s) to provide brightness that is not affected by a drop in battery voltage, and allows selectable levels of output.[citation needed] 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]

History[edit]

Coal miners wearing headlamps in 1946. At the end of the shift the lamps would be checked in to the lamp house for recharging and maintenance.

Head-mounted lighting likely started with candles, but problems with exposed flame and hot dripping wax motivated development of better alternatives.[citation needed] Carbide lamps were developed around 1900, and remained in use even as electric lamps appeared, because of poor battery life of the latter designs.[citation needed] The advent of high-efficiency LED lamps eventually displaced incandescent or combustion lamps.[citation needed]

Thomas Edison developed electric cap lamps for miners starting in 1914; by 1915, certain cap lamps were approved by the United States Bureau of Mines for safe use in gassy coal mines.[citation needed] These included features such as spring-loaded contacts to automatically disconnect broken bulbs.[2] These lamps consisted of a reflector and incandescent lamp and a separate belt-mounted wet-cell storage battery.[citation needed] The battery was 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.[2] This pattern became popular for similar lamps.[3] 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]

Gallery[edit]

Silva halogen headlamp primarily used for night orienteering with separate battery case and lamp 
Petzl LED headlamp with batteries and lamp combined 

Manufacturers[edit]

See also[edit]

References[edit]

  1. ^ a b c Swart, Peter K. (2002). Essential Guide: Caving. Stackpole books. pp. 34–41. ISBN 0811720527. 
  2. ^ a b Brune, Jürgen F. (2010). Extracting the Science: A Century of Mining Research. SME. pp. 35–40. ISBN 0-87335-322-6. 
  3. ^ "Mine Lighting". Retrieved 9 January 2012.