Abstract
When the relative index of reflection of dispersing particle to solvent is enough large and particle diameter is too small comparing wavelength of visible rays, Rayleigh scattering is observed and the scattering changes significantly by changing the particle diame-ter.Ultrafine barium titanate of average particle size 10nm which has been coated with surfactant shows good dispersion into insulated oil. This dielectric fluid is filled between two ITO coated glass plates to prepare thin film. When appropriate electric field to the forward direction of light is applied, particles make many long clusters of large diameter. Therefore, it becomes difficult for visible rays to pass through the thin film.As the application of this scattering, the light shutter has been considerd.
