Thermally induced switching temperature,spectral transmittance of thermotropic materials manufactured by a different mixing proportion of hydroxypropyl methyl cellulose(HPMC),sodium chloride and pure water was measured.Switching speed from transparent state to light scattering state of thermotropic layer in double glazing window was analyzed with numerical simulation.Radiation transmittance was tested on sample of thermotropic double glazing window,double glazing window and low-E double glazing window.Resul...