Improved Electrode Structures and Designs

Based on the molecular orientational tilting of LCs, various structures have been suggested to vary voltages onto LCs and thus change optical properties [5,6]. Choi et al. fabricated a two-dimensional LC microlens array using a surface relief structure of ultraviolet (UV)-curable polymer [5]. The microlens array cell was made with indium tin oxide (TTO) glass substrates. One substrate had a specific surface relief structure of the photopolymer used and the other had only the ITO layer. 

To develop a surface relief structure, the UV-curable polymer was spin coated on the substrates at a rate of 4000 rpm for 30 sec. The resultant thickness of the spin coated polymer film was about 3 pm. After a polymer film formed on the glass substrate, spatially modulated UV light was irradiated onto the film through a photomask. The photomask was designed to generate the intensity modulation of the UV light to form a pattern of microlens arrays. The irradiation led to the diffusion of monomers in the polymer composites from the unexposed to exposed regions. The result was the formation of a lens-shaped surface relief structure. 

A thin film of transparent n+ amorphous silicon 5.33 nm thick with an area approximately 1 mm x 1 mm, was deposited onto a glass substrate. Next, 

Liquid crystal microlens structure and two operating states. The crystal was aligned homogeneously on both surfaces. (Source Choi, Y., J.H. Park, J.H. Kim et al. 2003. Optical Materials, 21(1-3), 643-646. With permission.) 

Ground terminal connected to cover-glass electrode 

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