Is smart glass/film a safety glass?
Yes, smart glass/film is a safety glass. Being laminated, it prevents scattering of glass fragments in case of breakage.
What are the major reasons for using PDLC smart glass?
Enhanced security (since the glass is shatter-proof thanks to the internal plastic lamination)
Privacy (thanks to the scattering of light, essentially hiding whatever is behind the smart glass)
Glare reduction (again thanks to the scattering effect)
Reduction of the carbon footprint of the building thanks to the solar control, which reduces HVAC needs, both in summer and in winter
Reduced colour fading of interior furnishings and artworks, thanks to the rejection of UV
Creative marketing, since when the PDLC smart glass is off, the scattering effect creates a screen upon which you can project images.
How does smart glass/film works?
Smart glass works via electrical signal through activation of switches, sensors etc. Liquid crystal molecules turn to allow light to pass through and glass becomes transparent. It is opaque when not activated.
Are the only states of PDLC just ON and OFF?
No, the transmittance (level of transparency) of the PDLC can be varied from 0% in the OFF state up to any value you want until you reach the maximum transmittance (normally 70% or 80%). This is done by simply altering the voltage from 0 VAC up to 70VAC, which is typically the maximum recommended voltage. This can be done electrically with a variable isolating transformer, or electronically with a switched-mode smart glass dimmer.
Why does PDLC require a polymer?
The polymer allows the liquid crystals to be embedded into a film, which can then be sandwiched between panels of glass or plastic. The polymer has constant optical properties which do not vary across its structure, and hence is considered isotropic.
In contrast, the liquid crystal itself is anisotropic, since its optical characteristics are not constant across its structure, but rather can vary under application of an electric field.