'Smart' light?reflective windows based on temperature responsive twisted nematic liquid crystal polymers

'Smart' windows which reversibly increase their reflectivity upon heating are attracting considerable attention as devices for maintaining comfortable indoor environmental conditions. In this work, twisted nematic semi-interpenetrating liquid crystal networks lose order sandwiched between reflective linear polarizers. This 'smart' window decreases its transmission from about 50–10% over a wavelength range 400 and 1100 nm heating, resulting in the becoming darker reflecting more light. is potentially interesting energy saving applications where variation privacy visible light transparency states required.