Switchable glass, also known as Smart Glass, is a novel type of electrochromic glass that integrates a Polymer Dispersed Liquid Crystal (PLDC) film between two panes of glass and conductive layers. It is laminated under high temperature and pressure to form a monolithic structure. Users control the transparency and opacity of the glass by switching the electric current on and off.

As a special type of architectural decorative glass, also referred to as an electronic curtain, the principle behind switchable glass is that when the power is off, the liquid crystal molecules inside the glass are randomly dispersed, preventing light from passing through. When electricity is applied, the liquid crystal molecules align, transitioning the glass from opaque to transparent.