What are Smart Windows?
Smart Windows are windows which use a glazing material to
control the amount of light that is allowed to pass through the
The glazing material is often called “switchable glazing”.
These materials change their optical behaviour with
application of electrical voltage.
Active Smart Glass
Suspended particle device (SPD)
Polymer dispersed liquid crystal (PDLC)
Glass-ITO/LixWO3/PEO-LiN(SO2CF3)2/Liy(TiO2 – CeO2)/ITO/glass
Glass/ITO/polytoluidine/cellulose – polyacetate polymer/ Hy(TiO2 –
Ability to tune optical transmission from
clear to dark.
Low switching speed.
Lack complete opacity.
Requires electricity only to change
opacity, not to maintain
SPD – Suspended Particle Devices
Microscopic light-absorbing particles are dispersed in droplets within a film.
In the "off" state the particles are suspended randomly, making the window dark.
At moderate voltage is applied the particles align and permit light to pass through.
Angle prespective Voltage perspective
PDLC – Polymer dispersed Liquid crystal
Beats:1. Switching speed.
Opacity of dark state.
Most expensive option.
Switches to milky white in
less then a secund
Material When is
Requires power to
maintain the state
YES NO Widely used
(cheap), no „E”
for maintainig the
new glass must
SPD ON YES YES Fast, Clear to
Bad at blocking
PDLC ON NO YES External, Internal
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