Drivers can never have enough light. The same goes for visibility. The two are connected of course. But a whole string of other factors has to be right for good light to create good visibility.
Light itself is invisible. You can only see its effect once it hits things. When it comes to car lights, that’s mainly the road and its surroundings. So the road surface plays a major role. We all know how much brighter the light is when you drive on snow-covered roads. In normal weather conditions, center lines, road markings and marker posts make it easier for people to find their way through the night. Signposts and traffic signs become a lot more visible thanks to reflective film. Everything I’ve mentioned reflects light.
For drivers to benefit, the light needs to travel through the windscreen as freely as possible. So the windscreen should be tinted as little as possible. Today there are windscreens which block only infrared radiation but allow visible light to pass through. They’re the first choice for driving at night. Tinted film which impairs visibility even during the day isn’t good at all and therefore prohibited. “Adorning” the front side windows with the film is also off-limits by law. But even on the windows further back, the dark film will obstruct your view when you look over your shoulder or turn round to reverse for instance. And if on top of that the rear-view mirror and side mirrors – another element in this visibility system – aren’t clean, keeping an eye on the areas behind the car will be quite a challenge.
Film is one of those things that take visibility away from drivers. So are stickers. OK, some countries love emission and tax discs. Other countries love toll stickers. Nobody gets around these “adornments”. But what do you do with a dozen tollway permit stickers that have long since expired? Or the lights inspection disc from 2010, or the proud proof of your membership in an automobile club? If you have a number of these, they’ll surely obstruct your view. The Swiss police take this very seriously and fine anyone who goes a bit overboard on the disc front. That doesn’t apply to their own highway permit sticker, of course. But in Switzerland even a satnav mustn’t restrict your view through the windscreen.
Other factors for optimum visibility are fully functional windshield wipers and washer systems, with antifreeze and additives in the water often being underestimated.
But isn’t something still missing? Oh yeah, your eyes. Their incredible performance compared to cameras shouldn’t be diminished by glasses that are unsuitable for driving. Once again this applies to excessive tinting. But things such as good anti-reflective coatings and a wide field of vision also play an important role. Optical companies now even manufacture lenses specially optimized for driving.
Now there’s only one thing left in this holistic examination of visibility: car lighting itself. But there’s plenty of information in the carlight blog about that.