PDLC (Polymer Dispersed Liquid Crystal) Privacy Glass is made of two layers of transparent conductive film sandwiched with PDLC material.

 

The film is then laminated between two pieces of glass. When electricity is applied to the film the liquid crystals line up and the glass becomes transparent.

 

When the power is turned off, the liquid crystals return to their normal scattering positions and turn the glass from optically clear to opaque.