Headlamp

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. Headlamp performance has steadily improved throughout the automobile age, spurred by the great disparity between daytime and nighttime traffic fatalities: the US National Highway Traffic Safety Administration states that nearly half of all traffic-related fatalities occur in the dark, despite only 25% of traffic travelling during darkness. Other vehicles, such as trains and aircraft, are required to have headlamps. Bicycle headlamps are often used on bicycles, and are required in some jurisdictions. They can be powered by a battery or a small generator like a bottle or hub dynamo. The first horseless carriages used carriage lamps, which proved unsuitable for travel at speed. The earliest lights used candles as the most common type of fuel. Carbide lamp and Gas lighting The earliest headlamps, fuelled by combustible gas such as acetylene gas or oil, operated from the late 1880s. Acetylene gas lamps were popular in 1900s because the flame is resistant to wind and rain. Thick concave mirrors combined with magnifying lenses projected the acetylene flame light. A number of car manufacturers offered Prest-O-Lite calcium carbide acetylene gas generator cylinder with gas feed pipes for lights as standard equipment for 1904 cars. The first electric headlamps were introduced in 1898 on the Columbia Electric Car from the Electric Vehicle Company of Hartford, Connecticut, and were optional. Two factors limited the widespread use of electric headlamps: the short life of filaments in the harsh automotive environment, and the difficulty of producing dynamos small enough, yet powerful enough to produce sufficient current. Peerless made electric headlamps standard in 1908.