Two other types of switchable glazing are called liquid crystal device windows and suspended particle device windows (SPD). Liquid crystal technology has been used for some time in wristwatches and is gaining popularity as privacy glazing. A thin layer of liquid crystals is sandwiched between two transparent electrical conductors on thin plastic films, and the entire device is laminated between two layers of glass. When power is off, the liquid crystals are in a random and unaligned state. They scatter light, which makes the glass become translucent, thus obscuring direct views and providing privacy. This type is used most often in interior applications, including bathrooms, conference rooms, and changing rooms in retail stores.

SPDs, on the other hand, start out dark and become transparent when voltage is applied. They are made of an electrically controlled film with a thin, liquidlike layer in which molecular particles are suspended between sheets of glass. When electricity comes into contact with the SPDs, which have a transparent conductive coating, they line up in a straight line and allow light to flow through. Once the electricity is turned off, they move back into a random pattern and block light.