The Safest Headlights: Your Guide To LED, HID, and… Lasers
Okay, it’s time to dive into the interesting world of the headlights. Okay, they’re not interesting, but they are the most important safety feature in your vehicle. Well, that’s probably not true. But they are moderately important and definitely confusing. Which type of headlights are safest? What’s the difference between HID and LED? And which lights are the ones that blind you from the other side of the road? Rest easy. We have answers.
Halogen lights remain the default head lamp on the road. The system heats a small tungsten filament, the glow of which is then reflected onto the road. They emit that yellowish hazy light (around 3200 Kelvin). The bulbs are cheap to manufacture and easy to replace, but are estimated only to provide 1,000 hours of light. That means you’ll have to change your lights a couple times during the vehicle’s life. Halogen bulbs are also extremely inefficient. The tungsten filament reaches incredibly high temperatures – indicating that it’s wasting tons of energy. As we move toward hybrid and electric vehicles, maximizing the efficiency of electrical systems is paramount.
Additionally, government institutions are putting pressure on automakers to build safer vehicles. The Insurance Institute of Highway Safety actually requires excellent headlights for their TOPSAFETYPICK+ category. And if you think that’s an inconsequential distinction, go to a dealership and look for new vehicles without backup cameras. In 2014, the National Highway Traffic Safety Administration passed a rule demanding nearly all new vehicle have reverse cameras by 2018. So, don’t expect to see halogens for much longer.
HID (high-intensity discharge) appeared in the early nineties, becoming common in luxury and sport vehicles. Now, HID bulbs, sometimes called xenon, are offered as available equipment on most new vehicles. The light emitted by HIDs is higher in the colour spectrum than that produced by halogens. That means it appears whiter or bluish.
HIDs are also probably the lights responsible for blinding the hell out of you. When poorly installed, installed in a housing not designed for HIDs, or installed aftermarket without projectors, HIDs are dangerous for other drivers. A projector is a shutter that blocks part of the headlamps’ beams. Typically, the shutter blocks light from the upper and left portions of the beam. In other words, projectors stop light from coming across to the other side of the road and into drivers’ eyes. Projectors are included in every OEM HID setup.
You guys know all about negative electrons and photons, so you don’t need me to explain how LEDs (light-emitting diodes) work. It will suffice to say that the diodes convert energy into light far more efficiently than either halogens or HIDs. Further, they feature no moving parts, so they are highly durable. Plus, they last for 5,000 hours of use which should match the life of the vehicle itself. LEDs generally emit a bright white light, but you can them with different colour temperatures from yellow to blue.
BMW has recently introduced laser-powered headlights. Each light uses three lasers that are reflected through a series of mirrors toward a lens, producing a bright, powerful beam. According to BMW, laser headlights are 1,000 times more powerful than LEDs, last for 30,000 hours, and require 50% less power to operate. Plus, laser headlights can project information on the road like a HUD, identify and illuminate specific obstacles, and are connected to GPS to move with upcoming turns in the road.
With all of its capability and quantifiable advancements, it’s clear that laser headlamps will eventually displace LEDs as the go-to headlight technology. But hold on. Right now, laser headlights are exclusively available as a $10,000 add-on to the BMW i8 hybrid sports car. That may sound like a lot of money, but it’s a reasonable fraction of the i8’s $149,000 starting MSRP.
If, for some reason, you aren’t willing to drop 10k for marginally brighter headlights, you may have to wait a while. Eventually, the cost to make the laser lamps will come down and they will supplant LEDs. But for now, if you want to affordably illuminate the road, get yourself some diodes!