I always wondered if it would be feasible to make the headlights produce polarized light (e.g. vertical), and have windscreens filter out that polarization...

I always wondered if it would be feasible to make the headlights produce polarized light (e.g. vertical), and have windscreens filter out that polarization... I guess it would only work if the scattering of light off of whatever is being illuminated sufficiently depolarizes the light. Anyhow, I thought it was a neat idea when I was a teenager. There might be some issues with retro fitting the world's existing road vehicle fleet, but that's a deployment detail. :p