What Are Xenon Headlights

In the last few years, the types of lights you see on the road have changed with different levels of brightness, colours, styles and intensity. Newer and more modern models of cars tend to have a more distinct brightness and a white/blue glow - these are called xenon headlights. These new lights tend to be much brighter than the older models which use halogen bulbs or LEDs and are easier to make into stylish shapes and lines. These new form of car lighting are called xenon headlights or HID and in this blog, we're going to delve into what xenon headlights are, what benefits do they have over older halogen lights and LEDs and any other pieces of information surrounding these lights. 

 What is 'xenon'

The element used to create xenon headlights is called "xenon", it has the symbol Xe and it's the atomic number is 54. Despite it's most common public use is as a method of illumination it is, in fact, a noble gas. It's most notable feature is its ability to expel short wavelength ultraviolet radiation which is a bright blueish intense light when it's subjected to an electrical discharge. On its own, xenon is odourless, colourless, tasteless and non-reactive so you can't see xenon which can seem confusing considering its primary usage. 

That's the science bit done with.

Xenon has many uses ranging from lamps and illuminations, lasers and even as an anaesthetic. You may even find it's using in the world of sports doping. However, on the roads it's most common use is inside vehicle headlights.

 What are xenon headlights?

Xenon headlights are a set of lighting arrays which use xenon bulbs instead of traditional halogen ones. As we've learned, xenon headlights contain xenon gas particles which await an electrical discharge to illuminate and release the blueish light. Xenon bulbs are far more expensive and are typically either an optional (cost) extra or only come with prestigious brands such as MercedesBMW, Porsche and Land Rover.

From the outside, xenon headlights look more or less the same as halogen lamps or LED lights. It's at night time that vehicles with xenon headlights really stand out as they have a very distinct bright blue/white light which can shine up to three times brighter which is a godsend for the driver but perhaps for pedestrians and other drivers it's not so much of a gift.

Typically, cars with xenon headlights will still have a halogen bulb for high beam lights but there are some which are completely xenon which is called bi-xenon headlights.

 What are bi-xenon headlights

Bi-xenon headlights are basically the same thing as standard xenon headlights, however, there are now xenon headlights that will do both high beam and low beam as opposed to the halogen bulb doing high beams.

 What are the benefits of having   xenon headlights?

Using xenon headlights over halogen or LED has a couple of notable benefits. The biggest two are that they are brighter and can last a lot longer than LED and halogen lights. However, xenon headlights' biggest benefit in our opinion is the distance and width of the extra light xenon lights emit. Xenon headlights can be two to three times brighter than other alternatives giving drivers who are lucky enough to have them a much better view of the road, especially at higher speeds. The wider spread of light makes them even better to spot dangers on the side of the road and to some extent around bends.

Despite xenon lights being associated with a luxury vehicle, they are nevertheless the safest option, especially at night, to spot dangers much earlier and easier than with halogen and LED lights. However, they're quite expensive and the xenon element isn't exactly easy to find so they may be some way off being mainstream just yet.

What are the drawbacks of xenon headlights?

Xenon headlights have as many drawbacks as they do benefits and not only for the driver. Firstly, the element xenon is not in abundance nor is it easy to acquire making it quite a costly part to get for such a 'trivial' purpose such as car headlights. Adding these to a personal lease or business lease will increase the cost. Not only that, xenon headlights thanks in part to the element itself, is a complicated piece of equipment to put together which drives the cost up even further.

Perhaps the most vocal complaints towards xenon headlights are from other drivers and pedestrians - as we've noted, xenon headlights are very bright and can be dazzling if the automatic levelling isn't set correctly or if it's completely absent. Xenon headlights need a 'leveller' to ensure that they aren't raised too high - if they are aimed too high then they can dazzle other drivers and pedestrians which could lead to a real accident. However, it should be noted that the vast majority of xenon headlights do have automatic levellers. 

Lastly, xenon headlights go through an awful lot of headlight washer. This is partly due to how bright they are which means that any build up of dirt can affect the direction of the light and potentially raise them so that they dazzle other drivers. Headlight cleaners are in need because of law as xenon headlights produce over 2,000 lumens. We won't go into any more details on this as it's quite complicated but that is why xenon headlights need washer - the fact of the matter is that xenon headlights will use more of your washer and will likely splash back on the front of the car making it dirtier more regularly.

Click here to read the full ECE 48 law on headlight washers.