Field-Induced Refractive Index Change and Phase Shift

Field-Induced Refractive Index Change and Phase Shift 

In actual devices where the precise value of the phase shift is needed, the actual phase shift has to be calculated with quantitative numerical simulation of the director axis reorientation profile. For analysis purposes (e.g., estimation of required voltage, thickness dependence, etc.), the director axis reorientation profile that obeys the hard-boundary condition (0 = 0 at the boundary smfaces) can be approximated by a sinusoidal function of the form 

For STN cells, similar studies have identified the corresponding threshold voltages for various pretilt angles and initial twist angles. 

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