The characteristics and lifespan of different car lights

Knowing the lifespan of different car lights allows you to anticipate the replacement of this accessory. This offers the driver better safety, especially when driving at night. Note that this lifespan is not the same for all types of bulbs. It varies depending on the technology, conditions, frequency, duration of use, and manufacturing quality. You will therefore need to choose the most appropriate bulb technology among the many models of halogen, Xenon or LED. Here is what you need to know.

Halogen bulbs

The halogen headlights are old-fashioned incandescent bulbs. This is the oldest and most popular model. They work like those used inside homes, using a filament to produce light.

The halogen bulb is made up of a glass capsule. Inside, a gas called "halogen" both increases the internal temperature and creates a chemical bond with tungsten to obtain a brighter light. At the heart of the bulb is a straight tungsten filament made up of several coils stacked over a predefined length and diameter depending on the lifespan and power of the bulb: 35w, 55w, 60w, 65w, 100w, etc... When powered, the spiral filament will offer strong resistance to the electric current, causing heating and melting of the filament. The tungsten vapors in combination with the halogen gas will thus create a very powerful light.

The ordinary incandescent bulb is a technology that is disappearing from the automotive industry. In fact, the filament creates about 90% wasted heat and only 10% light. The halogen technology suffers a great energy loss due to red and infrared electromagnetic waves. This phenomenon is the cause of its high electrical consumption and short lifespan. These traditional filament bulbs have a lifespan that varies from 200 to 600 hours. Note that halogen bulbs are also very fragile and do not handle shocks and vibrations well.

Xenon bulbs

Among the different car lights, xenon bulbs are mostly used on high-end vehicles. Unlike halogen bulbs, xenon bulbs do not have an incandescent filament. They use xenon gas instead of a halogen gas, such as iodine or bromine. Xenon is a very rare gas on earth, part of the noble gases, inert in most chemical reactions.

The xenon bulb or discharge bulb has a complex operation and cannot work without an electronic management module called a "ballast". Equipped with a safety system, it acts as a "starter" amplifier and electronic regulator. When the bulb is turned on, an electric discharge of about 25,000 volts is generated by the ballast and applied between the two electrodes. An electric arc forms and ignites the xenon gas trapped in the small glass bubble, giving it this particular and slightly bluish lighting tint. A current of 85V is maintained to keep the electric arc at the predefined power. It is thus possible to adjust the power to obtain a more or less white light with a slight bluish or even purple tint, depending on the power of the current applied.

This explains the natural coloring of xenon headlights since they emit a blue-colored light, unlike halogen bulbs which emit a rather yellow color, and for which the white/blue lighting color is obtained using a colored filter incorporated at the factory around the bulb.

In summary, xenon bulbs are a complex technology but were a real revolution in their time, whether in terms of energy efficiency, power, or lighting color. Their tint is closer to daylight compared to that of the halogen bulb. The xenon bulb does not waste energy heating a tungsten filament, it only creates an electric arc to ignite the xenon gas, which requires less electrical consumption. Xenon headlights thus last longer than tungsten-halogen bulbs, about 1000 to 2500 hours for xenon and only 200 to 600 hours for a halogen bulb.

The main quality of xenon is its light intensity, with its 3000 lumens and minimal electrical consumption of 35W compared to only 1500 lumens with a halogen bulb and 55 watts of consumption. The xenon technology offers the driver better visibility and a clearer light beam. Note that xenon headlights certainly have good energy efficiency but suffer from significant electromagnetic losses, especially in the violet and ultraviolet.

Different car lights: LED bulbs

LED is the abbreviation of the English word: Light-emitting diode or diode électroluminescente in French. An LED bulb is an optoelectronic system that emits light when an electric current passes through it. It converts electrical energy into light with a precise chromatic radiation. Unlike xenon and halogen, all the magnetic waves emitted by the LED are in the spectrum visible to the human eye.

The origin of LED headlights

Originally, LED technology headlights were reserved for hyper sports and ultra high-end cars: Audi, Lexus, etc. They were sometimes only used for daytime running lights, turn signals, reverse lights and brake lights. However, since 2020, they are increasingly being applied to so-called "standard" vehicles. More and more vehicles offer the full LED option, that is, with the entire car in LED. A phenomenon that is understandable, given the potential of LED technology. It has one of the highest luminous efficiencies on earth, millisecond reactivity, and offers a beautiful look. The only downside for manufacturers: the cost is higher, compared to a car equipped with halogen bulbs.

Since the democratization of LEDs and technical advances, car LED bulbs have made a real leap forward. Nothing to do with the first LED bulbs put on the market! Remember the first generations of LEDs, sold as aftermarket. These LED bulbs were equipped with COB (Chip on board) chips with high luminous efficiency (100 Lm/W). Nevertheless, they did not provide good road lighting when used as low or high beams, because the light coming from the COB chips had too wide an angle.

Most COB LEDs sold at that time were a real ordeal for those who had the misfortune to encounter a car equipped with these LEDs. Dazzling was inevitable even on low beams! The light was so diffuse and imprecise that it could illuminate a very wide area up to the treetops without actually lighting the essential areas. This resulted in a very low concentration of light directed towards the road, poorer visibility of obstacles, a shorter illuminated distance, and an inability to pass the technical inspection. Unsatisfactory lighting that greatly contributed to the bad reputation of aftermarket LEDs at the beginning.

LED technology today

Nowadays, among the different car lights, LED headlights are of very high quality. They are mostly equipped with new generation High Power CSP chips, most of which exceed the 100 Lm/W barrier to reach up to 180 Lm/W. The most efficient CSP technology is of the PIG type (phosphor in glass). It consists of ultra-powerful and precise mini LED chips, arranged in eutectic connection on a very high-quality PCB board. A reduced and perfectly defined light angle allows for very precise lighting and ultra-high optical density. A real revolution in the world of automotive lighting.

Some LED bulbs achieve a very high luminous flux: up to 7500 raw lumens and 3900 measured real lumens with only 45 watts of electrical consumption compared to 2200 real lumens for a 100W halogen bulb with high consumption. The luminous power of a 35W xenon is around 3000 real lumens and some current LEDs are around 5000 real lumens.

Heat management, a real challenge

The biggest challenge with car LED bulbs is heat management. During operation, an LED chip generates a lot of heat at its core. A well-known phenomenon, called "the Auger effect", dissipates part of the energy as heat. With high-power LED bulbs, this phenomenon is even more true and accentuated. This is why, in the laboratory, researchers develop many cooling systems incorporated into LED bulbs.

There are two types of cooling depending on the luminous power of the LED bulb:

• Passive for low-power LEDs. Most often, they use cooling made of multiple aluminum fins or even copper braids made with a very fine mesh.
• Active, intended for LEDs delivering very high power, using fans coupled with "Cooling Tube" systems with superconducting liquid conduction.

The absolute key to maximizing the lifespan of an LED is directly related to its ability to extract heat. Good cooling of the LED increases its lifespan and luminous power. It is important to note that LED bulbs are the most durable bulbs. The lifespan of an LED bulb varies from 2000 to 5000 hours. This is enough to cover the entire lifespan of many vehicles, which means you may never have to replace the LED bulbs. It requires less energy than conventional systems, making its use attractive.

Halogen, Xenon or LED, you now know all the characteristics and lifespan of the different car lights.