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From: whit@milton.acs.washington.edu (John Whitmore)
Newsgroups: sci.electronics
Subject: Re: Bad News- Lasers replace Radar guns
Keywords: radar laser police
Message-ID: <1465@milton.acs.washington.edu>
Date: 19 Jan 90 07:58:27 GMT
References: <7263@lindy.Stanford.EDU> <13398@cit-vax.Caltech.Edu> <354@egrunix.UUCP>
Reply-To: whit@milton.acs.washington.edu (John Whitmore)
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Organization: University of Washington, Seattle
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	The possibility of filtering the reflected light so that only
a small part of the spectrum is actually measured makes jamming nearly
impossible for these babies; a laser (even a cheap diode laser) can
easily outshine the sun for watts/steradian/MHz_bandwidth.  
On the medium tech side, though, a diffraction grating could 
be built and blazed to take the laser beam and reflect it 
45 degrees from its incoming direction, so the reflection
always misses the sensor in the gun.  Diffraction gratings are cheap
and not difficult to build for long wavelength (like infrared).  
	So, you can get a large grating and employ decoupage
(basically making it part of the paint job).  It looks normal
in visible light, but the laser reflection misses the cop's gun.
	As for interfering with the police, that's a non-issue;
what American jury would support the claim that such a paint
job is interference?  The various governments, and their police, have
no particular rights to ease of observation of suspects.  It
is the suspects whose privacy rights are most clearly laid out in US law.
Canada, of course, has a different constitution.

I am known for my brilliance,         John Whitmore
 by those who do not know me well.