Glass electrodes sandwich an electrochromic layer, typically made from tungsten oxide, and an electrolyte, usually containing lithium ions. A voltage across the device makes ions move into the electrochromic material, changing its optical properties so that it absorbs visible and IR light.

How is smart glass made?

Typically, the liquid mix of polymer and liquid crystals is placed between two layers of glass or plastic that include a thin layer of a transparent, conductive material followed by curing of the polymer, thereby forming the basic sandwich structure of the smart window.

How does the switchable glass work?

When people envisage 'switchable' glass, what they're usually imagining is electrochromic glass. ... When a current is applied, the lithium ions and electrons are transferred from one layer to another, giving the glass a tinted effect. Once the current is stopped, they return, and the glass becomes totally clear again.