A smart window is a technologically advanced window system that contains glazing that can change or switch its optical qualities when a low voltage electrical signal is applied to it, or in response to changes in heat or light.

 

The most promising type of smart window is the electrochromic one, in which the transparency is regulated by applying a small voltage pulse between two transparent contacts. The transparent contacts as well as the active electrochromic layers are applied onto glass or plastic foils by advanced thin film deposition technology.