The light valve film (13) includes a liquid suspension dispersed in a polymeric matrix which has light-polarising particles of a size of 0.1 to 1.0 micron in a liquid suspension medium. The polymeric matrix is at most partially compatible with the liquid suspension medium, and its refractive index differs by at most 0.02 from that of the liquid suspension.
A polymeric dispersant is provided for keeping the particles in suspension. The liquid suspension is dispersed in the polymeric matrix at least in part in the form of an interconnected structure, and at least in part in the form of micro-droplets (18).
USE -Suitable for use in vehicle display devices, windscreen, rear-view mirror,sunglasses, optical shutters and windows for buildings.