Headlight bulbs - what types are there and which is best?

We look at the different types of headlight bulb and test 10 halogen units to find out which are the leading lights of the bulb world and which don’t make the grade...

Ford S-Max

Headlights have become brighter in the past few years, and at the same time many sources have reported an increase in problems with drivers being dazzled by the headlights of other vehicles.

The RAC recently surveyed its members and found that 16% of drivers had suffered a near-miss accident due to the brightness of another car’s headlights and that nearly two-thirds (60%) of drivers now struggle to tell if an oncoming car’s headlights are on dipped or full beam due to their brightness.

More than half of those who responded said the problem is getting worse. In fact, nearly 90% of drivers believe some car headlights are too bright, while 65% are regularly dazzled by dipped-beam headlights on oncoming vehicles and 49% are regularly dazzled by headlights in their rear-view mirror. Around 65% of people think car headlights are brighter than ever and more than half (51%) say cars with a higher ride height – such as SUVs – dazzle them the most.

However, motorists aren’t great at making sure their own cars don’t dazzle oncoming drivers; up to 71% could be dazzling other drivers because they don’t adjust their car’s headlights when carrying lots of passengers or heavy items in the boot, and while 25% have suspected their headlights were misaligned, only 18% took the car to a garage to get it fixed.

Jürgen Melzer, an automotive bulb expert, says: “When you’re dazzled by an oncoming car’s headlights, 90% of the time this is because the car has misaligned halogen bulbs, not over-bright xenons or LEDs. However, because the light from xenons in particular is whiter than that of halogens, people think they’re the ones dazzling drivers.”

Aftermarket bulb maker Ring highlights the importance of buying E-marked (UN standard) bulbs from reputable suppliers, because these have been designed to put light on exactly the right part of the road and tested to ensure they do so. “There are very cheap alternatives available, particularly from unknown sources online,” the company says. “Bulbs are safety-critical, and as such it’s not worth risking buying ones that haven’t been tested.”

Can you retrofit xenon or LED bulbs?

If your car originally came with halogen bulbs, you can’t retrofit it with xenons or LEDs, because the law states the replacement bulbs must have a filament. However, if your car already has xenon lights, they can be replaced with higher-specification aftermarket bulbs.

That said, a number of aftermarket bulb manufacturers now sell higher-spec halogen bulbs. Philips and Ring produce examples that project up to 150% more light onto the road, plus ones that emit a whiter light that’s closer to that of LED bulbs. This is more like sunlight, so it provides improved visibility.

Future developments in car lighting

Ford glare-free lights

Many new cars have headlights that automatically flip between dipped and main beam, and this technology is continually evolving. Ford has already introduced a glare-free light system for its LED headlights that adjusts the beam angle and intensity according to the car’s speed and steering angle (see the main image on this page), the distance to the vehicle in front, whether the windscreen wipers are on and how light it is outside. The latest development of this is from Audi and Mercedes-Benz, which now offer ‘matrix’ lighting that blocks out light only in a specific area rather than dipping the entire light beam. Audi and BMW also now fit laser lights to some of their range-topping models.

However, according to Melzer, it’s LEDs that are likely to bring about the most advances in lighting. “LED performance is increasing and the next generation of bulbs will have smaller optics, giving them a stronger, brighter and more efficient light source,” he says. “The smaller a light can be, the more versatile it can be, so it can be used in more places. For example, LEDs can be used in the grille of an electric car to provide information, such as how much charge the car’s batteries have left.

“And when driverless cars are introduced, communication with the outside world will be much more important. So the [LED] lights on these cars could be used to communicate with pedestrians to tell them if the car is slowing down or turning left or right.”

< Previous: What are the different types of car headlight bulb? / Next: 10 halogen bulbs tested, find out which is best >  

Page 2 of 3