Interesting article about NSA facility and capabilities
Ben Liddicott
ben at liddicott.com
Tue Mar 27 21:10:38 BST 2012
Sadly that is yet to be invented. One-way mirrors work because the
"observed" mirror side is light and the "observer" side is dark, so the
reflected light is much greater than the transmitted light in both
directions - but both sides can only see the "observed" side as it is much
greater in magnitude.
(Only one side has to be reflective - light can be absorbed in one direction
and reflected in the other, but the transmission will be pretty much the
same in both directions, modulo a small amount of cleverness with internal
reflection.)
Actually, having written that, I suppose a good question would be is a
partially mirrored glass permitted if the transmissivity is 70% or greater?
Certainly it will be much darker in the car than outside so it would still
work.
Just had a look at the construction and use regulations and this is not
mentioned, only the transmission of light.
http://www.legislation.gov.uk/uksi/1986/1078/part/II/chapter/E/made
So , yes.
Cheers,
Ben
-----Original Message-----
From: Roland Perry
Sent: Tuesday, March 27, 2012 4:56 PM
Is one-way glass allowed (<30% attenuation one way, 100% the other)?
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