A cheap, supplemental indicator of red or yellow lights:

How about a laser projected sheet of light that enters your car from projectors at the side of the road about 30-50 meters ahead of the intersection -- thus creating a brief by obvious flash of red on the INTERIOR of your car? The laser projector would be calibrated to switch off if any object in the 3 lanes adacent to it is moving at less than 20 MPH. An oscillating mirror would scan the laser across the plane that cars would penetrate well ahead of the intersection... and hopefully, the scanning action will make the light sufficiently diffuse such that pedestrians on the opposite side of the street (side where traffic is _departing_ intersection) would not be blinded by the laser light passing their way.

And for good measure, all the lasers of a city traffic control system could be slaved to a central computer that receives NORAD data. This would also help out in the new missile defense -- blasting incoming warheads with hundreds of converging lasers ... (OK, that last part is a little James-Bond/Science Fiction).
-- pathetic, Feb 06 2002

I was following you up to that last paragraph. I'm not sure how cheap this would really be, but given the cost of a traffic light anyway...

As for the mounting issues, why not just place the laser in the traffic light itself? If it's shining down into the face of the driver, you can bet it'll catch his attention.
-- phoenix, Feb 06 2002


Um, no. I think this would just serve to startle or blind the driver, or both. Even a paltry 1mw laser is quite blinding. Maybe just having the red traffic light strobe a little to annunciate might help.
-- bristolz, Feb 06 2002


If you do both, you might be able to trigger seizures in motorists who then go immediately blind.
-- Monkfish, Feb 06 2002


Yay!
-- thumbwax, Feb 06 2002


It would make driving in fog much more fun.
-- jutta, Feb 06 2002


could they wave about frantically and widen and narrow from plane to single line... People who drive with trance music compilation albums would have the best experience. People who drive on drugs wouldn't be doing too bad either, but I suppose we can't advocate that...!
-- sappho, Feb 06 2002


Bright streetlights on tall poles might be a cheaper way of going, admittedly with less possibility of being hacked by ravers.
-- pottedstu, Feb 06 2002


I had to bun this idea as an identical image occured to me today. Nobody would drive straight into a projected wall (internal or external), but people frequently violate stoplights. Furthermore, the exact controls of the intersection would be clear, no more "does that mean me?" , "is this my lane?" "where do i merge?", It's a little futuristic but i don't think it deserves such a round boning.
-- WcW, Feb 10 2009


I like it - but with a change - rather than beaming it at the drivers approaching the lights, it would be better if it were projected across the roadway (the plane could be emitted from one traffic light, and 'caught' by a matching arrangement on the other side of the road to avoid blinding pedestrians) Nobody would drive into the projected plane (after-all it's on red) and it would look like a Tron-like barrier, psychologically much harder to 'jump' than a regular red-light. Forcing cars to adopt barcode registration plates on the sides of their cars would also provide the police with a method of detecting violators, Tesco style. Lights using this type of signal would have to gently emit dry ice (to ensure that the barrier is visible) and so might not be much use in windy cities like Chicago.

It would only really work on stops/intersections where there's no right or left turn, otherwise you'd spoil the effect.
-- zen_tom, Feb 10 2009


The last two annotations before this one seem to interpret the idea as a volumetric projection, which is incorrect and not yet technologically feasible, both except when it's foggy outside.
-- notexactly, Apr 23 2019



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