Our knowledge of lasers has mostly been defined by sci-fi movies which have shown us the potentially lethal effect of using concentrated light as a weapon, while in the real world factories use industrial lasers to cut through thick steel as if it was polystyrene.
In both cases it’s not a very friendly form of light, so when a carmaker announces it’s going to start using laser headlamps in its cars – as BMW just has – one tends to get a bit squirmy.
But fear not. As tempting as it sometimes might be to have metal-melting headlamps to help clear the fast lane of dawdling drivers, there won’t be any such carnage on our roads. BMWs won’t be melting holes into your car at night, and nor will they sear your retinas.
Laser headlights are just the latest bit of high-tech to help drivers see further at night and make the roads safer. LEDs already offer several advantages in terms of light output and energy use, and lasers simply take that a step further.
When BMW’s petrol-electric i8 sportscar goes on sale next year in SA as the first production car to use laser lights as an option, its illuminated range will be 600 metres – double the range of LED lights.
Laser lights have far lower consumption than LEDs and they’re also a lot more compact; to get the same illumination from LEDs the diodes would have to be around ten times larger than they are now.
The automatic anti-dazzle function takes away the chore of constantly having to switch between low- and high-beam yourself. Sensors detect other cars on the road and “bend” the lights around them to avoid dazzling their drivers. Both headlamps are able to swivel vertically and horizontally and work independently of each another, so for instance when one headlamp dips to prevent blinding another car, the other can still be on high beam to illuminate the section of road next to the other car.
The lighting range is very noticeably better, and the greatly increased visible distance has clear safety benefits in terms of drivers identifying road hazards sooner and being able to react to them in time.
For now the laser light will be an option only on the i8, but the technology is sure to make its way into other BMWs in coming years.