Smart Glass

It is well known that indoor display of light susceptible materials
implicates use of filters, reduced overhead illumination, and
shields. My question is this, other than potential cost, have any
participants in this group encountered use of "Smart Glass" as an
alternative means of protecting artifacts from the effects of light?

I have been able to find many references to Smart Glass being used
to block light  present at exterior windows. However, for protection
against interior illumination, there appears to be only one
application of Smart Glass:

    <URL:http://www.stampsrart.com/rarityrevealed.html>

One question I have is, other than cost, why has this technology not
been considered by museums? A display case that used this type of
glass could keep an artifact protected in full bright light when it
was in a darkened state (thus eliminating use of filters, etc). With
a person present, it could be made transparent to allow only enough
the amount of illumination needed to comfortably view the
artifact--then darkened again.

If you have any knowledge of "Smart Glass" being considered for use
a part of a display case,  I would appreciate links or references to
the information.


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                  Conservation DistList Instance 20:49
                  Distributed: Friday, April 13, 2007
                       Message Id: cdl-20-49-021
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