Mirror State

Transparent State

Kazuki Yoshimura, Group Leader of the Energy Control Thin Film Group of the Materials Research Institute for Sustainable Development has developed a new thin film material for a switchable mirror that can be switched between reflective and transparent states. How it works? The thin-film uses a uniform layer of magnesium-titanium alloy on sheets of glass that can be sized to 60x70 cm and allows for a complete change from transparent to reflective and back again. The mirror is composed of two sheets of glass with the thin-film and an empty cavity between them. The empty cavity then can be filled with a gas composed of low-concentrated (about 1%) hydrogen and oxygen (concentrated to about 20%). The gas acts as a switch for the change in transparency.

The thin-film is created by a method of sputtering magnesium and titanium onto a plate. The combination layer has a thickness of about 40nm thick with another layer of palladium at about 4nm thick coating the surface which allows for the switch. This new type of development will have a major impact on energy conservation. AIST claims that the switchable mirror will reduce energy consumption by air conditioners by 30%. Also this material can be produced to fit homes and automobiles with the size standards due to the easy availability of materials.