BMW does around 500cd/mm^2 in the actual headlights. They can’t go higher because of regulations. In the lab they reached a maximum of 3000cd/mm^2, but they don’t say at what power consumption and what kind of cooling was necessary.
Laser diodes are more difficult to cool than LEDs. They don’t tolerate as high of a temperature.
EDIT:here is the link to article on the BMW headlights regarding their luminance values. Additional information can be found in this article.
I wouldn’t be surprised if they reached the peak luminosity in a short blink, so cooling was probably not necessary. Unless they kept one or more elements at sub-ambient temperature.
There is not a lot of useful information on that site. The lights look very big, so the lenses used are very big. It’s very possible though that their numbers are accurate.
I think they can do up to 30% wall plug efficiency without the phosphor. I guess now you can use numbers of a power LED that is available in blue and white to get the efficency using phosphor on top (you can also factor in that the phosphor is probably running at high temperature and thus lower efficiency).
I don’t hink it will be worse than our power LEDs at maximum power.
But our LEDs can be powered at less than maximum power leading to much better efficacies.
So the laser based lights will very roughly halve our sustained lumens while offering several times the candelas. Good, but for now not universally good.
Acebeam updated the stats on the page for the W10:
300Lm
High energy laser excitation phosphor produces white light
10,000 hours of service life
visible spectrum full coverage, no infrared and UV components
Class 3B
250000cd
angle :3degree
135G 150MM*25.4MM*33MM
1*21700 Battery 4800mAh
So it’s a class 3B laser that outputs 300 lumens of white light with 250k lux throw. With a beam angle of 3 degrees this is obviously only suited to looking at things very far in the distance (or for short ranged use as a pointer). A removable diffuser to allow the light to be used at short range might be nice.
According to FL-1 standard throw distance is √cd at 1m/0.25 because it considers throw distance the distance the light intensity will be 0.25 lux, wich is ridiculous.
But every flashight maker rate their products according to this imperfect standard, so does Acebeam.