Liquid Crystal Filled Polymer Structure (LiCFiPS) Devices consist of a polymer structure, which performs the desired spatial phase modulation of the incident light, filled with lqiuid crystal to permit modulation of this optical function. Potentially fabrication of this type of device, by established polymer hot rolling or embossing techniques, may be carried out at very low cost. Devices incorporating a complex polymer structure will inevitably have liquid crystal aligned at varying orientations to the surface. Switchable gratings with the liquid crystal aligned in the plane of the grating but either parallel or perpendicular to the grating rulings have been investigated as the two extremes of alignment. Good results have been achieved for parallel aligned devices, however devices with the liquid crystal aligned perpendicular to the grating lines show defects and inhomogeneities. Computational models of these devices show features that correspond well with the observed switching characteristics and have been used to explore routes to the design of improved devices. While such devices might not offer the ultimate versatility of matrix addressed SLM devices they do offer switchable optical devices at very low cost.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.