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"All the new traffic lights in our area have webcams pointed directly into the windshield of drivers stopped for the light. To what end, I don't know"

They could be webcams but the more common explanation is that they are visual sensors to detect cars in the turning lane, replacing the old wire loops in the pavement:

http://www.plan-bravo.com/lefty.html



They are not just to detect cars in the turning lanes but to detect whether cars are waiting for the light, and how long the queue is. This (supposedly) helps optimize traffic flow. I have my doubts as to whether it works any better than fixed timers. The claim that they are cheaper and easier to maintain than in-ground wire loops does seem believable.


It works better during off hours when there is little traffic.


Your explanation makes sense given most of the lights in question, but some have no turning lanes, such as at crosswalks. Perhaps bureaucracy has them required at all new lights regardless. Either way, government at work. :)

// Cool link, thanks. Shared with cyclist friends.


Well, some are pointed at the driver. Sometimes with interesting results...

http://boingboing.net/2008/10/27/german-traffic-cops.html




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