> They used a flashing IR LED to confuse the LASER type speed guns. The add
> said the laser gun takes several readings per second of the object that
its
> pointed at and measures the difference for a mph. The IR LED flashing
> confuses the laser's computer and no speed registers at the gun display.
>
> Does anyone know anything about how this works?
> Would the IRLED have to flash at a particular freq, if so what?

I not familiar with the exact design of radar speed guns, but I find it hard
to believe that pulsing IR of such low power would have any effect at all.
Radar uses microwaves which have wavelengths of several millimeters.  IR
LEDs usually have wavelengths below 1 micrometer.  There must be much more
IR power at longer wavelengths than that emitted by the hot radiator.

Did they give any reason why a pulsing IR LED should confuse the radar gun?


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

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