History of Headlights: Where Car Lights Begin And What They Are Today[1] [2] 

Car headlights have undergone a remarkable evolution over time. The quality of light has seen a remarkable increase during this period. The car experts from the Indianapolis dealer Indy Auto Man, briefly recall the whole story of car lights development. Find out what the designs of lighting devices were, why car headlights are so complex, and which headlights shine better now.

Where did car lights begin?

The first headlights essentially repeated household lamps. They also had a wick soaked in kerosene. These devices could not illuminate the road, but at least they indicated transport in the dark. A little later, acetylene torches replaced the wicks. They had to be periodically filled with calcium carbide and water. It was troublesome, but the quality of the lighting improved for the first time in the long history of these car components.

Electric headlights

Around the 1910s, electric headlights appeared on expensive cars like the Rolls-Royce Silver Ghost. Such devices began to illuminate the road much better. Although the bulbs were imperfect and weak at that time, engineers tried to use their light as much as possible. That is why the headlights of the early 20th century were so huge.

They achieved some efficiency, but progress brought another problem. Bright headlights blinded oncoming drivers, which affected traffic safety. Bosch engineers came up with the solution: they released a lamp with two spirals that could be switched on independently. Today, such a thing will not surprise anyone, but in 1919, it was a revolutionary innovation.

Thanks to this invention, drivers can now utilize both low and high beams. And in the middle of the 20th century, another idea was born: to make an asymmetrical beam of light. Since oncoming traffic moves to the left, the beam was directed more downwards on this side. And on the right, where the roadside is, the headlights were allowed to shine further. The innovator was the Cibié French company, which developed a prototype of such headlights. As a result, they became the standard in Europe, but in America, cars lit the road symmetrically for a long time.

Halogen lamps

When engineers solved the problems with a temporary car driver’s blinding, they began to look for ways to make the light brighter and, at the same time, increase the service life of the lamp. In 1962, the Hella company released the first halogen lamps – in them, the bulb cavity contained gaseous compounds of iodine or bromine. They reduced the intensity of tungsten evaporation from the filament, making it possible to heat it more strongly without losing the resource, which means such a lamp shone brighter. As a result, the halogen served about twice as long, and the light output increased by about 1.5 times.

LED headlights

At the beginning of the 21st century, LEDs became more widespread. They are slowly but surely replacing traditional light sources – primarily due to their efficiency (economy) and durability. It is not surprising that LED lights have appeared in automotive lighting technology. Read a detailed comparison of LED vs. halogen headlights.

LEDs could provide at least the same illumination level, not requiring complex ignition units. The resource approached the car service life, and energy consumption decreased.

Like everything new, LED headlights began to appear first on premium models. But today, LEDs have replaced conventional incandescent lamps in mass-market cars. Although they also have their drawbacks. When overheated, the LED loses brightness, so powerful light sources in headlights require good cooling. Well, the size of the LED, comparable in brightness to the xenon arc, is also not small. Nevertheless, the engineers came up with an alternative: rather than relying on a single large lamp, they decided to utilize numerous smaller sources.

Matrix headlights

Then, the lighting engineers came up with a great idea: each of the many LEDs can illuminate its section of the road and be turned on and off independently. This is how matrix headlights appeared. They differ from conventional LEDs in their progressive control system.

A camera mounted on the windshield of a car monitors the traffic situation and determines the presence of other road users: for example, oncoming traffic or a passing vehicle that you have overtaken. The headlight control system is capable of recognizing the LEDs responsible for illuminating the area near other vehicles and switching them off, thus maintaining light only in free-from-vehicle areas. Thus, the driver can see the road perfectly but not blind others.

Laser headlights

Laser headlights can be called the most advanced type of head optics today. However, they do not emit laser beams. They are directed inside the headlight at the mirror with a layer of phosphor – a substance that, when interacting with the laser, begins to emit light. Therefore, it is the mirror that is considered the source of radiation in a laser headlight.

What does the use of lasers in headlights give? First of all, the distance that a car can illuminate has increased. And today, these are the brightest headlights. Moreover, the light can be collected into a narrow beam, so lasers are the ideal high beam. As a bonus, energy consumption has decreased. As well as the headlight size, compared to any other type. The main disadvantage is the huge price.

So different headlights

The intensity of headlight beams is not solely determined by their type – even halogen headlights on the same vehicle model can emit different levels of brightness. The reason is the differences in light distribution and brightness standards for different countries.

The European standard implies an asymmetrical light distribution spot. If you shine such a headlight on a vertical surface, you will notice that the right side of the beam shines higher and the left – lower. This geometry has practical significance: obstacles and pedestrians appear on the side of the road (that is, on the right with right-hand traffic), and road signs are also located there. But on the left is oncoming traffic, whose drivers cannot be blinded.

In the American standard, the beam is symmetrical. The headlights shine at the same distance, directing the main part of the light directly in front of the car, and the border of the light beam is blurred.

It’s all about the American organization of traffic. For example, in the USA, we are much more liberal about the location of road signs – the plate will not necessarily be on the right side of the road. And it also needs to be illuminated. In contrast to symmetry, the US standards more strictly limit the brightness of headlights – the light of American cars is traditionally considered dimmer.

However, this is true for reflector optics, which are used less and less in modern cars. LED and matrix headlights allow you to precisely control the light beam, so the problem gradually disappears.

Summing up

• Over the years of automobile development, the headlights have come a long way, from kerosene lamps to high-tech devices with built-in lasers and computer control.
• When creating headlights, engineers solve two opposing problems: to illuminate the road as brightly as possible and to blind oncoming drivers as little as possible.
• State standards regulate the brightness of automobile lights and their distribution on the road. These rules differ from country to country.
• The technology of headlights seriously depends on car price. Budget models are still produced today with halogen, which must be adjusted manually. On the other hand, some cars cost less than a pair of laser headlights on a luxury model.