As being part of the "enemy" I can tell you that both Radar jammers and Laser jammers are illegal in most states under state law, and they violate FCC rules since you become a radio transmitter when you install a jammer, without an FCC license.
With that said, lets talk about Radar and Laser forms of energy.
Radar is a burst of Microwave energy that is broadcast out much like a shotgun blast, hits a target vehicle (s)and returns a signal that is determined to be not only the strongest signal, but the fastest target signal as well. For example you have a mack truck and a K1200S. The mack is doing 60 MPH and the K1200S is doing 120MPH. The radar will most likely try and return a reading from the mack truck at first, then convert over to the k1200S at 120MPH. It is then up to the trained and certified operator to discern what vehicle is doing what speed.
Laser is much like a high power sniper rifle. Depending on the manufacturer of the laser, it fires off anywhere from 8 to 20 bursts of light energy in a millisecond. The laser is target specific (often equipped with a gun like scope with cross hairs or a red dot) and can acquire a vehicle as far away as one mile if properly aimed. I personally have acquired a car as far away as 4900/5000 feet away. The Laser gives not only the speed of the vehicle, but the distance it was acquired as well.
Fellows, the bottom line is if you are going to speed, be prepared to face the consequences of your actions...