Abstract: A method for preparing a film suitable for use as the light-modulating unit of an SPD light valve, which film comprises a cross-linked polymer matrix having droplets of a liquid light valve suspension distributed in the cross-linked polymer matrix. The light valve suspension comprises particles suspended in a liquid suspending medium. The method comprises admixing a UV cross-linkable liquid oligomer or polymer and the liquid light valve suspension, emulsifying the resulting admixture to form an emulsion of the liquid light valve suspension in the UV cross-linkable liquid oligomer or polymer, and cross-linking the UV cross-linkable liquid oligomer or polymer while the mixture is in the form of a thin layer of the emulsion by exposing the layer to UV radiation or to an electron beam, such that the film is not damaged due to such exposing. The oligomer or polymer and the particles are free of deleterious effects on one another.