'Automobile Headlamps'

• While it is common for the term headlight to be used, headlamp is the technically correct term for the device itself, while headlight properly refers to the beam of light produced and distributed by the device
• History of automotive headlamps: The first electric headlamps were introduced in 1898 on the Columbia Electric Car from the Electric Vehicle Company of Hartford, Connecticut, but they were optional
• In 1912, Cadillac integrated their vehicle's Delco electrical ignition and lighting system, creating the modern vehicle electrical system
• The 1924 Bilux bulb was the first modern unit, having the light for both low (dipped) and high (main) beams of a headlamp emitting from a single bulb
• The standardized 7 inch (178 mm) round sealed beam headlamp was introduced in 1940, and was soon required for all vehicles sold in the United States
• Halogen lamps were prohibited in the United States where non-halogen sealed beam lamps were required until 1978
• In 1940, the US government mandated a 7 in. (178 mm) round sealed beam headlamp on all automobiles. Headlamp styling in the United States virtually ceased for many decades after this event
• Functions and fitment: A headlamp system is required to produce a low and a high beam, which may be achieved either by an individual lamp for each function or by a single multifunction lamp
• Most low beam headlamps are specifically designed for use on one side of the road or the other, i.e., the light is distributed with a downward/leftward or rightward (depending on the side of the road being driven on) bias to show the driver the road and signs ahead without blinding oncoming traffic
• The differences between the SAE and ECE headlamp standards are primarily in the amount of glare permitted towards other drivers on low beam (SAE permits much more glare), the minimum amount of light required to be thrown straight down the road (SAE requires more), and the specific locations within the beam at which minimum and maximum light levels are specified
• Headlamps must be kept in proper alignment (or "aim"). Regulations for aim vary from country to country and from beam specification to beam specification. US SAE headlamps are all aimed alike, regardless of mounting height

Name:     (required)
Email:    (required, not published)
Comment: