On Feb 22, 2010, at 5:04 PM, Keith wrote:
Although
by now the LED light output in general is high enough that
they are used in traffic lights (a lot of the traffic lights around
here (Zurich) use LEDs). Regards, Alex.
For what it's worth, I'd imagine
most cities either already have, or are
starting to use LED traffic lights. We have had LED traffic lights in
Pittsburgh, Pennsylvania, USA for at least a couple years. I might even
be willing to bet that most(all?) new lights installed around here are
LED.
I see incandescent traffic lights every once in a while, but rarely. Most
everything I've seen for the past few years is LED.
I see quite a few incandescents up here in northern MN still; it's rumored
that the harsh winters cause problems with the LED ones - they just don't
output enough heat, so snow and ice can build up and obscure them.
Maybe the current generation have built-in heaters to combat this (which still
doesn't make them pointless, I suppose, as LEDs should need far less 'bulb
changes')
cheers
Jules