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Computer simulations are made of polarizing microscope textures of supramicron-sized nematic droplets with director configurations which commonly occur in polymer and other dispersions. The simulations are computed from polarization rotations and phase shifts caused by nonuniform optical anisotropies of the nematic structure in liquid crystal droplets. The treatment is limited to the case of spherical droplets which are optically soft so that reflection and refraction at the droplet surface, as well as refraction on any internal structure, can be neglected. Simulated polarizing microscope textures of four different director configurations at different orientations are presented graphically. The simulated pictures are shown to compare well with observations of actual nematic droplets viewed under crossed polars.

The response times and operating voltages for light shutters made from polymer dispersed liquid crystals' are studied. Alterations in the resistivity of the polymer binder are made by varying the degree of cross -linking to demonstrate and quantitize the strong effect of resistivity on the switching voltage. The voltage response from transitions in the nematic director configuration is studied in radially configured droplets and the molecular anchoring energy at the droplet wall is measured. Measurements of the relaxation time, response time, and voltage response are also reported on uniformly elongated and aligned droplets to study the effect of droplet shape. The results of these measurements are compared with calculations based on simplified models for ellipsoidal shaped droplets with major and minor axes a and b respectively. Response equations in terms of the aspect ratio C =a/b are experimentally examined.

Liquid crystal materials have advanced sufficiently such that very thin microdisplays can be made. A vertically aligned cell having sufficient speed for field sequential color has been designed. Simulations are shown, along with preliminary experimental results. The experimental results show a photopic contrast greater than 1000:1 at an F/# of 3.3.

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