Is photo radar used for speed enforcement in any community on the west side of St. Louis?
Recently, I drove I-70 west from St. Louis. Somewhere near the airport a man on the right shoulder raised a hand held unit that appeared to flash, much like a camera. I then realized that he was wearing a very low profile, hard to notice uniform. Apparently, he was law enforcement. Within two miles, three police units were busy on the side of the road with traffic stops. Any ideas about what the flash unit was? Could it have been a type of speed enforcement? Could it result in a speeding summons in the mail?
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Yes. It is the next generation lidar speed system. It works similar to radar only it uses the doppler shift of light beams instead of microwaves. You were hit with an Infra red flash of between 900 and 1200 nm, although it could be any frequency. Just for fun, you can get a piece of ceramic that will resonate at double the frequency so the IR light becomes visible and you know when you’ve been had. It halves the wavelength to about 560 nm in the yellow to green range.
Re. getting the summons in the mail. tht depends upon your state. Usually they just use the handheld units to call ahead to a trooper down the road and have him pull you over.
Psst… There are more IR cameras on you than you think.
It certainly sounds like a speed enforcement device, though I haven’t seen any in use yet. There is considerably more concern for the red-light cameras.
The red-light cameras result in mailbox summons; I expect that the lidar would as well.
The police use the lidar unit the same way they use radar. They pull you over or use a conventional traffic stop. The neat feature of lidar is that it can take a picture of you while it is recording your speed. With the old radar, the trooper had to call ahead with a description and any license plate info he could grab. This is much better (for them).
Speed cameras are in use in Phoenix and other cities. They use conventional X or Ku band microwave radar to trip the camera with OCR capability. You get a love note in the mail.
Relax. If you did not get pulled over you are in the clear. You were under the enforcement threshold.
@worriedguy 2 GAs. Thanxs. Can you further elaborate on how and what ceramic to use? On the day in question I saw the flash with the naked eye. I suppose the ceramic would make it easier to see.
Hey @UScitizen
At the time one of my coworkers gave me the 75mm square piece. I was just looking to find the name and came across this stuff. It is a dye that absorbs IR and fluoresces in a different wavelength. You can paint your dashboard with it.
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