White ECD using zinc compound

Adiabatic planning for building is a good idea for saving energy and favor of earth environment. Windows of housing are important for providing natural lighting and ventilation, however, they obstruct adiabatic planning. Light-controllable windows, which are called `smart windows' are of use and one solution for adiabatic planning. Smart windows can control the intensity of light as user pleases. Their driving mechanism uses some kind of chromism, thermochromism, photochromism and/or electrochromism. Electrochromic device (ECD) can control both light-holding and heat-radiation by electrochemical redox. Most ECDs using transitional metal oxide which have been studied have colored states such as blue or brown. We consider that white ECD is more suitable for living spaces. In our study, white ECD materials were developed for smart-windows by using a zinc compound. This window changes between a transparent- state and a white-state, like a Japanese-SHOJI', in response to electric conditions. This smart-window can also control light-intensity (transparency) by both applied pulse width and pulse voltage, and no power is consumed to maintain a state. A test trial device which was assembled by our project can change its states between transparency and white, in stable, during over 500 trials.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.