How does smart glass work?

Smart glass, which is also technically known as switchable glass or electrochromic glass, operates by utilizing advanced material science to alter its light transmission properties when an external stimulus is applied. The most common form of electronic smart glass utilizes Polymer Dispersed Liquid Crystal (PDLC) technology embedded directly inside the glass unit. In this design, a microscopic liquid crystal film is sandwiched securely between two transparent conductive layers of plastic or glass. When the electrical power switch is turned off, the internal liquid crystal molecules are arranged in a completely random, unaligned state. This random configuration scatters incoming light rays in every direction, causing the glass to appear completely frosted and opaque for total privacy. However, the instant an electrical voltage is applied, an electric field passes through the film, forcing the liquid crystal molecules to instantly snap into a perfectly straight, parallel alignment. This precise alignment allows light rays to pass right through without scattering, turning the glass completely transparent.