The Influence of the Inter-pixel Region in Liquid Crystal Diffraction Gratings

An important problem associated with multiple pixel liquid crystal (LC) modulators is the incidental diffraction due to amplitude and phase gratings formed by the improperly modulated regions between electrodes. This problem becomes more of an issue as the resolution of the SLM increases and the size of the pixels begins to approach the size of the inter-pixel spacing. We perform 2D director profile modeling in LC diffraction gratings to take into account the electrode structure and fringing electrostatic fields. The electrooptical properties of the grating are simulated and compared with experimental data. This information can be used to design addressing structures with enhanced fill factor. The results obtained could be beneficial for applications in image processing, laser beam control, steering and adaptive optics.