HIROSHI HOSAKA (Professor, Graduate School of Frontier Sciences, University of Tokyo)

Diversification and miniaturization are progressing in mobile PCs, information appliances, environment sensors and healthcare monitors. Recently, PC, PHS and GPS navigation system have been installed in a wrist watch. Another example of specific application is studies of crow¡Çs behavior tracking the position and stay time using a PHS terminal. The most crucial problem in such miniaturization and diversification is to ensure power source. So far, high-density chargeable batteries (secondary batteries) and small-size fuel cells have been studied. The author and his colleagues propose micro-automatic power generators which transform energies wasted from machines, humans and animals to electric energy. This automatic generator has advantages not only to avoid nuisances related to battery exchanges but it helps reduce environmental burden because battery disposal doesn¡Çt occur.