Transmaterial

By using a thin film of magnesium-titanium alloy, the National Institute of Advanced Industrial Science and Technology has produced a switchable mirror that can be easily transformed between reflective and transparent states. The mirror window is 60 x 70 cm in size, and has been designed to reduce energy consumed by air conditioning systems in buildings and automobiles by over 30%.

In the development of early prototypes, Kazuki Yoshimura and his team focused on the use of thin films made of magnesium-nickel alloy that behave as switchable mirrors. Unfortunately, these first versions all had a yellow tinge in their transparent state. The newly developed thin film, however, is made of an alloy of magnesium and titanium, which does not turn yellow in its current configuration. The switchable mirror consists of two layers of glass enclosing a cavity and coated on their interior surfaces with the alloy film. A gas that contains hydrogen at a low concentration of about 1% or oxygen at a concentration of about 20% is introduced to the cavity to activate the switching behavior. [via AIST; suggested by Dace Campbell, Seattle.]