Basically a set of powerful IR LED transmitters.
The most common misconception about Laser (or Lidar) is there is a tight beam being reflected back so its really hard to aim to jam. In fact the reflection is a massive scattered light pattern, and the Lidar electronics do some whiz bang doppler calculations with the reflected light waves to calculate your speed.
The Lidar receiver is susceptable to jamming by these IR LED transmitters, as well as reflected sunlight, and halogen lights which both have enough IR light in them to throw the lidar gun off. Essentially the Lidar gun seeings the 'extra' IR light coming in and can't calculate the speed properly, usually throwing up an error (error 7 - to much ambient light is the one I think our guys get in NZ).
In testing my jammer the most common reaction I got was for the cop to pack up and move 500 metres along the road. So it seems they are trained to just move when they get this error.
As for them working, well, the Rocky Mountains stuff doesn't. Its pure BS. But my current unit is a CMB, very dumb, always on, twin head, but no rear protection. It seems to be 100% effective (from the front). The one I've ordered is a Bel model, theres also an Escort model available, as well as the M-10 which is a little older. Watchout for renamed Rocky Mountains stuff, its basically empty except for a LED and buzzer.
The photo traps over here are similar, station wagon with tinted windows, a camera, and a Ka band radar constantly on firing at about 22 degrees onto the road. Best defence for those is a good detector. My Bel 980 gives me around 200-500 metres warning depending on the camera setup. Cheap radar detectors (such as Uniden) will only go off once you're on top of the camera.
Nefarious, its not hard to make something that'll set of radar detectors. Hell, most cheap detectors in cars coming the other way leak enough RF to set them off mine on a regular basis.
Originally posted by StSanta
So how do laser jammers work? DO they work?
And how about beating those damned photo traps? We have vans here with toned windows. Got some device and a camera sticking out and you get flashed if you're driving too fast. Father got ticketed this way - they just plop a fine into your mailbox.