Liquid crystal displays (LCDs) constitute an important class of modern display tech-nologies. Their light-weight nature, coupled with their favourable power consumption char-acteristics make them useful in applications ranging from large area projection displays tosmall electronic devices such as digital watches and calculators.Despite being the market leader in the display industry, traditional configurations ofLCDs suffer from serious drawbacks such as having a very narrow viewing cone. Newerconfigurations of LCDs, however, employ the in-plane switching (IPS) mode and its deriva-tives. These provide a much wider viewing cone with lower degradation of image qualityas one moves off the central axis.IPS pixels have a unique configuration as they contain the electrodes on only one sideof the domain. The electrodes are arranged in an interdigitated pattern and producean electric field that varies periodically in space parallel to the substrates and decaysexponentially in space along the through-plane direction.The highly non-homogeneous nature of the electric field makes the simulation of theelectric field within an IPS domain more challenging as a minimum of two dimensions isneeded to model the electric field with sufficient accuracy, in contrast to the electric field inthe twisted nematic (TN) mode that may be modelled in only one dimension. Traditionalapproaches have employed an iterative technique wherein the Gauss law equations aresolved for a pre-determined director configuration and the electric field thus obtained isemployed to calculate the new director configuration over the domain. The iterations arecontinued till convergence is attained.Our method involves calculating the electric field by means of a semi-analytical expres-sion for an electric field produced by interdigitated electrodes and using this expressionto calculate the domain configuration. This methodology is advantageous in terms ofcomputational time and effort as it gives a possible way to do away with the back andforth iterations involving the dynamic equations and the Gauss’ law equations. In thiswork, we attempt to look at dynamic characteristics of the liquid crystalline domain in anIPS-LCD. Metrics were evolved to quantify the deformation in the domain. Finally, thesemetrics were used to examine the dependence of the equilibrium orientation on the domainthickness, electrode width, electrode spacing and electric voltage applied.The results show good match with the trends that can be expected from theoreticalconsiderations. The variation of the domain deformation characteristics with the changein the geometric and physical parameters is along expected lines. For instance, increasing the voltage results in the domain getting deformed to a much greater extent and the defor-mation to penetrate deep within the domain. A greater pixel depth with the same valuesof the other parameters results in more of the domain staying undeformed as the electricfield only penetrates upto a fixed distance into the domain. Increase in the electrode spac-ing was not found to make a significant contribution to the deformation while increasingthe width of the electrodes increases the area affected by the electric field and thus, thisincreases the overall deformation.To conclude, the framework provided here is a valid first step in evolving a completesoftware package to model deformation characteristics of an LCD pixel. The code is flexibleenough to accommodate different LCD configurations and thus, may be used to model avariety of other LCD configurations also. A parallel development of an optics code using amatrix based method may be used to model the propagation of light through the domainand this may be added very easily on top of the existing framework to create a completepackage for analysing the electro-optical properties of the LCD.
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