Fit your windscreen with a fine, transparent LCD "grid" with embedded light sensors and some electronics to produce "anti-dazzle" windshields.

Whever a pair of headlights is directed at you and are bright enough to ruin your night vision, the electronics sense where you are looking, and "grey" out the brightest portions of the light in a path directly in line with your head so you dont get blinded. It only reduces the amount of light coming in, and a fine grid wont blot out critical details (hopefully) that you might miss.

Also would be good with things like low-angle sunlight, etc.

The little light sensors could be like those embedded car-antennas...
-- smurfzilla, Jun 04 2004

LCD Sunvisor http://www.halfbake...idea/LCD_20Sunvisor
same thing on the sunvisor [FarmerJohn, Oct 04 2004]

corner-cube reflectors and cats eyes http://www.bikexprt...lectors/reflwrk.htm
[Ling, Jul 04 2005]

That seems to be a very complex system for a modest goal. if you could have the windshield have other functions (after all it is a computer display) like showing maps and darkening on bright days and maybe even sending messages to other drivers it would be more justified.

I read about a scheme (I think in PopSci in the 80's) that would have both windshields and headlights polarized so that lights shining directly at you would not be glaring, but light bouncing off streets or other cars would be depolarized and would not be affected.
-- macrumpton, Jun 06 2004


//lights shining directly at you would not be glaring//
only if the light source was polarised. I don't think that applies to either incandescent or flourescent lamps, and it certainly doesn't apply to the sun.

croissant for the idea by the way.
-- spacemoggy, Jun 06 2004


a far a polarizing windshields and healights goes... I'm not positive but I'm pretty sure if you have two polarized films and one is turned 90 degrees, you block out all light. That would be bad if someone installed their headlights wrong and you can't see them at all.
-- 88supra, Jul 15 2004


The amount and nature of the object tracking, gaze and ray-tracing involved in this idea is a bit far-fetched, especially with multiple light sources, at least for now.
-- bristolz, Jul 15 2004


But I think this could work as follows:

The driver first has to wear some glasses with small corner-cube reflectors (see link). These reflect light back to where it came from.

Each reflector will shine on the inside on the windscreen at almost exactly the same two spots that your eyes can see the headlights.

Then the thin film p-n junction light sensor can feed the location of increased irradiance to a computer that checks the distance between the two spots is correct before dimming that area.

A corner-cube reflector can also change the polarisation of the light, which might assist in checking irradiation from the inside of the screen.

Alternatively, just mount a row of corner-cube reflectors around your windscreen, facing forwards. Any offending driver, who doesn't dip, or has incorrectly adjusted headlights will automatically see the results.
-- Ling, Jul 04 2005


//That seems to be a very complex system for a modest goal// Obligatory bun.
-- coprocephalous, Jul 04 2005


// the electronics sense where you are looking

How? A wibnitron?

// only if the light source was polarised. I don't think that applies to either incandescent or flourescent lamps, and it certainly doesn't apply to the sun.

No. LCDs have two polarizing filters already. When the liquid crystals twist, they twist the polarization of light, too, causing it be blocked by the second filter.
-- omegatron, Dec 12 2006


yeah yeah man for truckies, i wish i had a dollar for every time some FU#%$#&%&ER, beamed me up, the bastards, never dip their lights, and if ya give em the whole ensemble of high-beam +4 daymaker's they run off the road, or chase ya down or silly crap like that, i know a good thing to do with tailgaters who wont dip their lights, ya empty a small bottle of diesel out the window into the slipstream, most of it will disperse, but some gets on their windscreen, and is difficult to get off, and even harder to see through properly, so only do this if you are on a duel carriageway, and there's no oncoming, oh and you didnt hear it from me.
-- Stork, Dec 13 2006


You scare me [stork]

Anyhoo, why doesn't anybody use photochromatic windshields???
-- Custardguts, Dec 13 2006


My guess is cost, they are pretty much a fixture on all rearview mirrors now. Another would be regulation, in the US you cannot have tint on the Windscreen(could impact visibility)
-- jhomrighaus, Dec 13 2006


Can't you people just wear sunglasses?
-- shapu, Dec 13 2006


At Night? While Driving?
-- jhomrighaus, Dec 13 2006



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