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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."
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
Beamers always looked nice, now with the optional tiny sharks inside the headlamps they'll be simply irresistible.
What would PETA say?
You can't handle the truth.
Put them on the Hyundai Tiburon.
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.
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.
Read this sentence from the last paragraph of the article; "Importantly, therefore, before the light from the tiny laser diodes is emitted onto the road, the originally bluish laser light beam is first of all converted by means of a fluorescent phosphor material inside the headlight into a pure white light which is very bright and pleasant to the eye." Therefore no lase light escapes the headlight. This is in effect laser stimulated florescence. The one number they miss in the article is what is the conversion ration between the light incoming to the phosphor and the light given off by the phosphor. It could be 100% but I don't know. After this conversion the light is probably no longer coherent and will disperse like a headlight should.