The characteristics of high powered laser is a small beam, good direction, energy can be concentrated to a relatively small area, so it is not like an ordinary light source that illuminates a large area (the answer says to be able to laser beam, laser beam expanding, but after and ordinary light what different?)
Alone any car, the driver’s eyes must be higher than the light, if all cars are almost the size, as long as the high powered laser direction with a certain downward angle, then the laser light is not possible to direct the other driver’s eyes, this is also thanks to the good laser direction.
However, different car lights of different height, a large truck headlights is likely to be much higher than that of a car headlight so to make high powered laser more secure, also need the maximum height of the entire automobile industry agreed a laser lamp, which is lower than the lower edge of the smallest car front windshield the glass.
Light propagation in the fog will have a reflection, if the energy is large enough, the driver’s eyes, the basic car is a high powered laser, the driver to see the road? Similarly, energy is too small, and impenetrable fog.