Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!umich!wsu-cs!egrunix!besler
From: besler@egrunix.UUCP (Brent Besler)
Newsgroups: sci.electronics
Subject: Re: Bad News- Lasers replace Radar guns
Keywords: radar laser police
Message-ID: <349@egrunix.UUCP>
Date: 17 Jan 90 16:03:38 GMT
References: <7263@lindy.Stanford.EDU>
Reply-To: besler@unix.secs.oakland.edu.UUCP (Brent Besler)
Distribution: na
Organization: Oakland University, Rochester, MI
Lines: 15

I posted on rec.autos and sci.electronics about the laser speed measuring device
back in November.  I got some info from a Popular Mechanics editor on it.  It
is telescopicly aimed.  To the best I can determine it uses a GaAs laser diode
around .9 microns in wavelength(just beyond the visible in the IR).  It is pretty
low power since it is a Class I laser device.  The detection apparatus is going to
have to be pretty sensitive on it, since reflection from a car won't be that high.
It works on computing succesive distances rather than a doppler effect.  It runs
about $3000, so it is about 3 times more than current radar units.  It can't 
be used while moving currently since it can't determine the police cars speed
yet.  It should be possible to reduce the effective range by using daytime
headlight.  They have a high output(halogen particularly) around .9 microns.  
The beam is very narrow about 0.2 degress, so a detector will be useless, before
it is too late.

							Brent H. Besler