Polarization, transmission, and small-angle scattering of light by a polymer film with elongated droplets of nematic liquid crystal

Abstract

An optical-mechanical model has been developed to describe the transmittance, polarization and small-angle distribution of light scattered by an uniaxially-stretched polymer film containing the elongated ellipsoidal droplets of nematic liquid crystal. It is based on the approximations of Foldy-Twersky, anomalous diffraction, and single scattering. The spectral dependences of transmittances and polarizing abilities of the polymer dispersed liquid crystal films have been analyzed as well as the small-angle intensity distribution and the polarization degree of scattered light depending on the film thicknesses, refractive index of polymer matrix, sizes of droplets, their anisometry parameters, concentration, polydispersity, and optical axes orientation. The optical characteristics of films with homogeneous and inhomogeneous interfacial anchoring at the surface of liquid crystal droplets have been considered. The transmittance and polarizing ability of the films have been studied as functions of the angular aperture of the system recording scattered light. Highlights: Polarization degree >0.97 of passed light is possible in spectral range 0.45-0.7 m Polarization degree >0.95 and transmittance 0.5 are achieved at angular aperture <3º Stretched films with monodomain and bipolar structures are effective light polarizers