Privacy at the flick of a switch is possible with Switchable glass. This is state of the art laminated glass with a liquid crystal interlayer between two sheets of glass.
In clear mode an electrical current is passed through the interlayer which aligns the microscopic crystals along a number of parallel axes, thus allowing vision through the glass.
When privacy is required the current is switched off and the crystals scatter into a random formation which prevents vision through the glass.
It is suitable for a variety of applications in security, architectural and display projects and as it is laminated it also provides good acoustic properties.