BMW developing laser headlights

From Popular Science:

Calling laser headlights "the next logical step" after the LED headlamp, BMW has announced that it will be rolling out laser-based illumination on its next-gen BMW i8 concept and will further develop laser headlight technology for extension across its various models. Why? It saves fuel. And presumably because laser headlights is something we've all secretly wanted on our European sports cars since MI6 tricked out 007's first ride.

Click to expand...

Catch BMW's buzzword-infused press release here.

BMW is claiming 170 lumens/watt, which seems suspiciously high, especially since the method of going from monochromatic (blue laser) source to white involves the all-too-familiar phosphor approach used for LED's. I'm guessing that's the potential efficiency of the laser itself, in the lab, running at low power, with infinite heatsinking.

It seems like you throw the advantage of coherent light out the window once you send the beam through a phosphor media, which will naturally scatter it. I also suspect that the hoopla around the supposedly smaller source in a laser vs a LED will not translate into any significant reduction in volume.

Comments? Sounds like interesting tech, but I doubt it's going to stomp all over other technologies anytime soon...

I've got most of the same questions about this as you. I don't see the point of starting with a coherent light source when the headlight pattern calls for a decent divergence angle. Somehow I think I remember the press release or Autoblog's blurb about it saying something about highlighting objects with the light. Maybe that means some DLP-type thing. Or maybe I am just too tired. Still seems pointless beyond the ZOMG LAZORS factor.

Well, BMW got the kids excited about the whole halo thing, why not fricken lazers too?
I went to a truck show and there was a vendor selling complete headlight replacement systems. It was 4 or 5 hundred dollars per light ---- for an ordinary halogen replacement with a halo. At least they said it met DOT regs.

So along with butchered halo kits, bootleg HID kits, we can look forward to hatchet job laser kits. Nice.

Wow, it takes a very thick filter to screen out all the hype and BS in that press release! From what I can see, they're probably looking at using laser diodes to excite a downconverting phosphor. The primary advantage would be efficacy and packaging, though perhaps there are some optical techniques that would work better with the output characteristics of a setup like this than with what the press release amusingly calls "conventional" LED headlamps. I think it is an error to dismiss the idea based on a laser's coherent beam; such a beam is several stages aft of the front lens of the headlamp -- by which I mean it's not necessarily relevant to what is emitted from the front of the headlamp.

Hilldweller said:

I went to a truck show and there was a vendor selling complete headlight replacement systems. It was 4 or 5 hundred dollars per light ---- for an ordinary halogen replacement with a halo. At least they said it met DOT regs.

Click to expand...

It's possible there's a halo-ring light set such as you describe having seen that is legally compliant, but I have yet to see it, which I humbly contend is saying something. I always see an enormous amount of blatantly noncompliant garbage at SEMA, much of which is claimed, with straight face, to be legal.

LukeA said:

Maybe that means some DLP-type thing.

Click to expand...

I had been thinking the same thing. I've been trying to find some reading material about this type of lighting, but am coming up with blanks....although I haven't tried searching the SAE and Visteon archives yet.

Scheinwerfermann said:

It's possible there's a halo-ring light set such as you describe having seen that is legally compliant, but I have yet to see it, which I humbly contend is saying something. I always see an enormous amount of blatantly noncompliant garbage at SEMA, much of which is claimed, with straight face, to be legal.

Click to expand...

This dreck was disguised as HID, actually. They did their best to hide it all in a projector and word it that way. The emphasis was on the halo and projector though.
Headlights are bling in this country; just read the chat forums on enthusiast sites.
We're doomed if BMW does this. The Chinese bootleg product will surely fry the oncomer's retinas.

Hilldweller said:

Headlights are bling in this country; just read the chat forums on enthusiast sites.

Click to expand...

Too true I gave up discussing HID conversions in my truck's forum, as it went from "it's legal, you just don't understand!" to "so what that it's illegal".

Also interesting how the article is technically correct even in the title, while also managing to be misleading. Certainly allows for more Bond references.

/me thinks of a screen of phosphor, imaged onto the road ahead. Depending on which parts of the phosphor the laser lights up, the image of the lit phosphor gets projected onto the road. For lightign up pedestrians, a normally unlit area of phosphor is lit up that corresponds to the assumed location of the pedestrian. Same goes for blanking highbeams that perhaps teh old fart driving the car forgot to turn off. Perhaps the car will autodetect the location of other autos and blank the high beam that goes towards those cars. I don't think the DLP idea posited earlier is too far off.

I think you'll probably be proven right. The fully adaptive, real-time camera-driven "glare-free high beam", as it's called, is already a reality. This laser/phosphor idea would be another way of implementing an idea already on the roads, probably with greater flexibility and system simplicity.

bshanahan14rulz said:

/me thinks of a screen of phosphor, imaged onto the road ahead. Depending on which parts of the phosphor the laser lights up, the image of the lit phosphor gets projected onto the road. For lightign up pedestrians, a normally unlit area of phosphor is lit up that corresponds to the assumed location of the pedestrian. Same goes for blanking highbeams that perhaps teh old fart driving the car forgot to turn off. Perhaps the car will autodetect the location of other autos and blank the high beam that goes towards those cars. I don't think the DLP idea posited earlier is too far off.

Click to expand...

If the phosphor screen is precisely shaped and coupled to a precision optic, I can see a rapidly-scanning laser (or lasers) on a DLP-type arrangement (or some less exotic oscillating mirror/crystal arrangement) performing this sort of functionality. I just can't imagine it being more energy-efficient than LED. It would take the coherence of a laser to pull this trick off.

(or some less exotic oscillating mirror/crystal arrangement) performing this sort of functionality

Click to expand...

Possibly not that complex. You might have several lasers assigned to various zones on the remote phosphor lens, and they simply cut off or turn on in a specific zone to project a particular pattern of illumination on a roadway. Galvos / oscillators aren't exactly the most rugged of devices, although they are simple to drive. They would also produce motion artifacts unless driven at very high speeds, or perhaps the remote phosphor would blur this out.

Laser lights

I just read a publicity squib that says Laser headlights will be introduced within a couple or three years, that the lights themselves are "1000 times brighter and 100 times smaller" than the traditionally square cells used in LED lights. That's a lot of zeros..... what does anyone know about them?
LEDs are supposed to be able to put a lot of light on the road and, unlike HID lights, don't need any high voltages to start delivering.... I wonder what sort of electrical background is needed by these glass-melting lasers?

Shall we be replacing our LED flashlights by lasers? If there was a flashlight that was 1000 times brighter and 100 times smaller, I suppose it would probably be 10,000 times more expensive, too!

Re: Laser lights

I'd rather not regularly expose my eyes to lazed energies.
Next well be hearing about melted eyes.

I'll stick with led's and unharmed vision lol!

Re: Laser lights

artec540 said:

I just read a publicity squib that says Laser headlights will be introduced within a couple or three years, that the lights themselves are "1000 times brighter and 100 times smaller" than the traditionally square cells used in LED lights. That's a lot of zeros..... what does anyone know about them?
LEDs are supposed to be able to put a lot of light on the road and, unlike HID lights, don't need any high voltages to start delivering.... I wonder what sort of electrical background is needed by these glass-melting lasers?

Shall we be replacing our LED flashlights by lasers? If there was a flashlight that was 1000 times brighter and 100 times smaller, I suppose it would probably be 10,000 times more expensive, too!

Click to expand...

I would be interested to know the lumen watts (ie, how many lumens of light for 1w of electricity) they are expecting to make. 1000x brighter quite possibly means 1000x more electricity, which just is not going to happen with current batteries. (10 minutes of googling told me that LEDs and Lasers are about the same efficiency, no idea how accurate my 10 minutes of googling is)

Re: Laser lights

Awesome! Hahaha

Re: Laser lights

Well I guess technically a 1 micron square chip is 1000x smaller than a 1mm square chip, but at only 170 lumens per watt, you're still going to need more than one of them to create enough light to be usable for driving. That's assuming the chip can be continuously driven at one watt without melting itself. Though I bet all of the "throw hounds" would love it.

http://www.engadget.com/2011/09/06/bmw-developing-laser-headlights-officially-over-leds/

Re: Laser lights

Lux vs. Lumens.

There's a big difference between intensity and overall light output.

1000x intensity just means that the light from a laser comes out in a very narrow beam - useless for headlights.

Re: Laser lights

http://www.motorauthority.com/news/1065710_bmw-develops-laser-headlight-technology

Having already announced the introduction of full LED headlights in its new 6-Series range, BMW is moving onto the next wave of advanced [FONT=inherit ! important][FONT=inherit ! important]lighting[/FONT][/FONT] technology for cars: lasers.

[FONT=inherit ! important][FONT=inherit ! important]BMW[/FONT][/FONT] engineers are currently working on the introduction of [FONT=inherit ! important][FONT=inherit ! important]laser[/FONT][/FONT] light in car [FONT=inherit ! important][FONT=inherit ! important]headlights[/FONT][/FONT], with the aim to improve safety as well as efficiency.

Laser lighting is radically different from sunlight, and also from the various types of artificial lighting in common use today.

For a start, laser lighting is monochromatic, which means the light waves all have the same length. It's also a "coherent" light source, which means that its waves have a constant phase difference. As a result, laser lighting can produce a near-parallel beam with intensity a thousand times greater than that of conventional LEDs.

Also, the high efficiency of laser lighting means that laser headlights have less than half the energy consumption of LED headlights, in the end helping to save fuel. Whereas LED lighting generates only around 100 lumens (a photometric unit of light output) per watt, laser lighting generates approximately 170 lumens.

Additionally, laser lighting diodes are very small. With a length of just ten microns (µm), laser diodes are one hundred times smaller than the square-shaped cells used in conventional LED lighting, which have a side length of one millimeter. This opens up all sorts of new possibilities when design cars.

And there's no risk to humans, animals or wildlife when used in car lighting. This is mostly due to the light not being emitted directly, but initially converted into a form that is suitable for use in road traffic. The resulting light is very bright and white.

The technology is expected to debut in production form on the upcoming 2014 BMW i8, although it has already been previewed on the i8 Concept we saw recently. Note, laser lighting is already used in a variety of consumer products, namely CD and DVD players, however, in most cases it goes unnoticed by the user.

Re: Laser lights

offthetrail said:

http://www.motorauthority.com/news/1065710_bmw-develops-laser-headlight-technology
Also, the high efficiency of laser lighting means that laser headlights have less than half the energy consumption of LED headlights, in the end helping to save fuel. Whereas LED lighting generates only around 100 lumens (a photometric unit of light output) per watt, laser lighting generates approximately 170 lumens.

Click to expand...

Cree XML = 231 lumens per watt

Perhaps they have upped laser efficiency since then as well?