LASER bicycle lights Is there any reason there are not yet LASER bicycle lights, given some cars already have them?

It makes more sense in bicycles, has they have not a 12V bulky battery like a car, and are more energy efficient than LED lights.

I am speaking about lights which directly illuminate to the front or rear, not things that project a straight line, or a bicycle or a lane on the floor?
The most important part of a vehicle light is the optics because you want a beam with a precise shape and distribution in order to illuminate the road evenly, without wasting light into the sky or blinding people coming in the other direction.

These optics are very difficult and expensive to design. It is easy to make a circular lens which will throw half the light into the sky and blind people coming towards you. A proper beam, which results in even illumination of the road regardless of distance, has to distribute light in a special way which is very un-even: low power at close distances, high power at long distances, a sharp cutoff to avoid blinding other riders, and it has to have the proper pattern in the horizontal direction also:



This lamp costs € 189 which is quite expensive. These beam shots tell the rest of story. It is very difficult to do a sharp cutoff without wasting light.

Important: beam accuracy depends on the ratio between optics size and light source size. The smaller the light source the better. A tiny point light source would be ideal, and it has to be positioned accurately at the focal point of the optics. A larger light source can work, but the size of the entire optics assembly has to be scaled up proportional to the size of the light source. If the optics size is constrained (ie, you're not riding with a 8 meter wide telescope) then the larger the light source, the more inaccurate the result.

Now, you mention laser lights. The reason these are interesting for car lights is not the efficiency. No-one cares about the efficiency of headlights when the car burns tens of kilowatts just to move. Besides, I found a 160lm/W efficacy figure for laser headlights. LEDs can do that already. The interesting bit is that laser-excited phosphor lights can create a really tiny point source, which is what makes these excellent optics possible.

But do you need that on a bicycle?

If you travel at 250 km/h in a fancy sports car, you'll need a light that illuminates the road very far away, at least several hundred meters. But a bicycle is a bit slower, so most people will be happy with a light that allows them to see, say 50m ahead, maybe 100m going downhill, and that can already be done with LEDs at a much cheaper price than laser.

There is also the fact that an optic that can aim a beam at long distances has to be aimed where the beam needs to be, which means a computer and several precision actuators. Since a bicycle leans in turns there would have to be extra actuators to compensate for that. It gets silly very quick.

Conclusion: even if laser-excited phosphor lights get cheap in the future, their advantage is enabling fancy optics you don't need on a bike, not efficiency. LED efficiency is driven by very strong economic factors (ie, the lighting industry) so LEDs will get more efficient. I don't think you'll get laser bike lights anytime soon.