One way to prevent an accident is to make cars as visible as possible to give drivers more time to make a decision. This improves the driver’s visibility and increases road safety from this perspective. However, the white light dazzles other road users much more than conventional halogen headlights. Older road users in particular suffer from excessively bright lights. Incorrectly adjusted or dirty headlights also dazzle oncoming traffic.
The most important facts in brief: Why headlights dazzle
- LED and xenon headlights shine much brighter than halogen.
- White or bluish light is perceived as more unpleasant at night.
- High luminance with LEDs due to a lot of light and a small illuminated area
- Dirty headlights can be up to four times more blinding.
- Fogged headlights
- Incorrectly adjusted headlights with too high a luminous cone.
Blinded drivers are a safety risk that must be taken seriously. On a dark road, the human eye can have poor vision for up to 30 seconds when suddenly blinded by an oncoming vehicle. This is related to the receptors in the retina. If they are tuned to nighttime light and suddenly a very bright light hits them, they are overwhelmed.
Drivers who are blinded by oncoming vehicles often cannot see anything for fractions of a second. This effect increases with the age of the driver.
For people between 60 and 70 years of age, this can last two seconds. In this time, the car travels 56 meters at highway speed. In addition, the number of problems with twilight vision often increases with age.
- Do LED headlights dazzle more than others?
- Free-form reflectors vs. lens projection
- Adaptive headlights: Low beam instead of daytime running lights
- Incorrectly adjusted headlights
- Dirty headlights
- Fogged headlights endanger driving safety
- Causes of fogged headlights
- Possible consequences: the dazzling effect
- Tips for drivers: How to protect yourself from glare in traffic.
Do LED headlights dazzle more than others?
LED and xenon headlights can dazzle oncoming traffic for different reasons. One reason is the color of the light. LEDs shine with a color temperature of about 6,000 Kelvin, making them very similar in color to daylight. However, the human eye adapts to natural lighting conditions and perceives the bright light as inappropriate when driving at night. Xenon headlights also shine much brighter than halogen and have a color more similar to daylight.
Free-form reflectors vs. lens projection
The other problem with LED headlights is their light intensity. LEDs can produce up to ten times as much light per watt as halogen lamps. In addition, LEDs are very small. This means that a large amount of light is emitted from a small area. This increases the light density, and the human eye is more easily dazzled. But not all LED headlights are the same. In an investigation, there is a clear difference between two designs with regard to the problem of glare.
LEDs with free-form reflectors have a larger light beam. The light distribution is more homogeneous and the luminance is lower. This reduces the glare effect. Lens projection systems, on the other hand, allow a direct view into the light emitter. The headlights are often smaller and the luminance higher. For this reason, such LED headlights are significantly more dazzling.
Adaptive headlights: Low beam instead of daytime running lights
Automakers like to advertise adaptive headlights that prevent oncoming traffic from being dazzled. However, this only applies to the high beam. The problem remains with the low beam. For this reason, car manufacturers should use headlights with free-form reflectors for the low beam if possible.
Drivers frequently report in Internet forums about malfunctioning assistance systems for high beam. The assistant recognizes oncoming traffic too late or reacts too hesitantly. In the worst case, the assistant does not dim the headlights at all. It is important to distinguish between real glare from oncoming traffic and what is subjectively perceived as too late dimming. If in doubt, drivers should always take their vehicle to a workshop. A faulty high beam assistant significantly dazzles others and thus increases the risk of an accident.
In addition to low beams, other LED lights on the vehicle often have a dazzling effect, for example daytime running lights. It often dazzles strongly due to its small surface area. Those who do not have glaring LED headlights should therefore switch from daytime running lights to low beam as early as possible. Many drivers also feel dazzled by modern brake lights and taillights.
Incorrectly adjusted headlights
One of the most common reasons for blinding oncoming traffic is incorrectly adjusted headlights. If they shine too far up, this can blind other motorists. This applies both to vehicles in front and to oncoming vehicles. The corresponding degree number, which describes the inclination of the light cone, is usually printed on a sticker on the headlamp housing. In the case of vehicles without automatic headlight range adjustment, the owner should check regularly, ideally in the fall, to ensure that the lights are set correctly.
Dirt on the lenses of headlights can also dazzle oncoming traffic. This applies primarily to light soiling. They cause the headlights to dazzle up to four times as much as clean lights. In the case of even greater soiling, on the other hand, it is predominantly the luminous intensity that suffers.
Fogged headlights endanger driving safety
Fogged headlights are not just a visual problem, they actually endanger driving safety. This is because the small drops of water inside the lamp housing can cause a dazzling effect and impair the driver’s vision.
Causes of fogged headlights
The most common cause of condensation inside headlights is moisture that has entered the housing from the outside. In other words, there is a leak through which water can penetrate. This happens during heavy rain or also during car washing. Especially when washing the car with a high-pressure cleaner, the risk of water penetrating the lamp housing is relatively high. High-pressure cleaners are often used incorrectly, they are held at too short a distance to the headlights. This can result in tiny cracks in the headlight gasket. Leaks can also be caused during lamp replacement.
Normally, however, the moisture escapes again in dry weather conditions. Modern headlights also have a ventilation system. The ventilation system ensures that the moisture gets back outside and the headlights dry from the inside. A possible cause of constantly fogged headlights can also be that the ventilation system is no longer working, because something is clogged, for example.
Fogged headlights endanger driving safety
Fogged headlights are not just a visual problem, they actually endanger driving safety. This is because the small drops of water inside the lamp housing can cause a dazzling effect and impair the driver’s vision. But how does the moisture in the headlights occur? What can be done about fogged headlights?
Possible consequences: the dazzling effect
The small water droplets not only degrade the luminosity, they can also dazzle other road users and therefore increase the risk of accidents. If the fogging is very severe, the headlights can even become completely blind. Then the luminosity is actually drastically reduced.
Tips for drivers: How to protect yourself from glare in traffic.
- Make sure your windshield is clean.
- People who wear glasses should also make sure that the lenses are clean.
- Do not look directly into the headlights of oncoming traffic.