BMW Working On Laser Headlamps

MrSeb writes "LED headlamps are only just trickling onto the market — mostly on high-end cars — but now it seems a certain German automaker has plans for laser headlamps. 'Laser light is the next logical step in car light development ... for series production within a few years in the BMW i8 plug-in hybrid,' says BMW. Lasers have the potential to be simultaneously more powerful, more efficient, and smaller than other headlamp types. Before you get too excited, though: the output of laser headlights will be modulated for safety."

Re:Ah wonderful

[mcvos]

Its not like the HID lamps fucking blind you enough as it is, we need LASERS! so we can be blinded up to 2 miles away

My thoughts exactly. Biking in the dark and rain, oncoming headlines make it impossible to see anything other than painful light surrounded by a lot of dark. I'd like to see headlamps toned down a bit.

Re:why lasers?

[Megane]

Headlights should fade out in a couple hundred yards, not be blinding people from 10 miles away.

That's called "collimation", which is not an inherent property of laser light, just a typically desirable one. Laser light is monochromatic (one frequency) and coherent (all waves in the same phase). Collimation is the focusing into a narrow beam. Some laser types are inherently collimated, some aren't.

Re:why lasers?

[jittles]

The laser plugs aren't to save electricity. The laser burns so hot that you get a much better "spark" if you will. In other words, more complete combustion and therefore more power, less gas fumes in exhaust, and (I am no expert but I imagine) less CO as well.

Re:Yeah thanks.....

[Solandri]

Because they are more efficient for the same brightness levels, which is especially important for electric cars, since they'll be less of a drain on the batteries.

The typical sedan needs about 20-25 hp to maintain highway speeds. That's 15-19 kW. Car headlights are about 50 Watts each. If as a post above says, laser headlights represent a 70% improvement in efficiency, that means you could replace 100 Watts of headlights with about 60 Watts of laser headlights - a 40 Watt savings.

40 Watts is 0.2%-0.3% of 15-19 kW. If you take the Nissan Leaf which has a nominal 70 mile range at highway speeds, saving 40 Watts will get you about 800-100 feet (240-300 meters) in additional range on a full charge compared to regular halogen headlights. So they represent a trivial amount of energy savings which nobody is going to notice, even on an EV.

That said, BMW is a luxury brand (in the U.S.). So they'll probably be able to sell enough of these to rich people (early adopters) to justify the R&D costs, and it'll help improve the state of the art for everyone. But don't make the mistake of thinking that this will result in any significant energy savings for EVs.