I'd be willing to be that placing a semi-reflective glass wedge in the optical path ahead of the scope's front lens would defeat such laser detection systems. Any incoming light not reflected off the wedge's front surface (and
There is a easily-available kind of architectural glass called "Azurelite" (PPG Industries) (read: "Cheap") which would transmit less than 2% (single pass) of 900nm infrared in a 45 degree "brewster window" configuration. For two passes, that's 0.03% reflection even if the underlying scope optics reflected 100%. In other words, vastly less reflection than even a black piece of paper. ----- Original Message ----- From: <keyser-soze@hushmail.com> To: <k92t3rd@hushmail.com>; Cypherpunks <cypherpunks@cyberpass.net> Sent: Wednesday, September 20, 2000 21:58 PM Subject: Re: Re; cover your glass perhaps
trapped in an adjoining baffle) would almost surely be reflected off the wedge's other front surface denying the laser's operator enough of a return signal to work with.
That the lasers are probably working in the IR (so as not to be easily detectable by the snipper) makes the wedge even easier to use as it needn't appreciably reduce the visible component most useful to the sniper.
At 12:30 PM 12/31/99 -0500, you wrote: Old news: See below
---------- Reply to ---------- Date: 31 Dec 1999 04:20:45 -0000 Subject: cover your glass From: lcs Mixmaster Remailer <mix@anon.lcs.mit.edu> Reply-to: lcs Mixmaster Remailer <mix@anon.lcs.mit.edu> To: cypherpunks@algebra.com
Re: acoustic shooter detection systems in LA
Just FYI: Some time ago I read of the development of sniper-detection systems which looked for reflections off the 'scope glass.
This probably isn't ready for prime time, being in development maybe a year ago, and isn't mentioned in the article, so you're probably safe taking your time, sighting in.
BMGMonger -----------------------------------------------------
Here in my stack of oddball periodicals I have a copy of the July/August 1998 issue of Revue Aerospatiale A french aerospace journal, wherein we have an article Lasers: Hard-Hitting Watchdogs
The best way to dissuade snipers is to deprive them of their impunity by ensureing they know that their exact location has been pinpointed. CILAS demonstrated this at Eurosatory with its directed-optics laser detector- the first production unit intended ultimately for delivery to the French army. This ground-breaking technology can be expected to bring other developments in its wake.
It goes on;
Quietly, free from media hype, things (this is in ref to background on why snipers are bad) have suddenly changed since a prototype of the SLD400 was received by the French armed forces. Behind this mundane designation lurks a device capable of detecting, locating and indentifying the optics with which snipers are equipped.
More;
The scope of application of the SLD400 is much wider and can include the protection of VIPs and pinpointing sharpshooters of the binoculars of terrorists preparing criminal acts. (it actually says that)
The article goes on to describe building databases of specific optical device signature and such. So that they not only know that you are there, they also know what you have deployed to better asses threat level and so on.
Assume they know, always.
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