Limits of applicability of the direct ray approximation in modeling optical properties of liquid-crystal diffraction gratings

Abstract

Using computer modeling, we estimate limits of applicability of the direct ray approximation in modeling the optical properties of liquid-crystal diffraction gratings with continuous spatial modulation of the local optic axis orientation in a liquid crystal layer. The data presented concerning the influence of the spatial frequency and character of modulation of the local optic axis, as well as the magnitude of birefringence of the medium, on the accuracy of the results obtained in this approximation are also useful in considering birefringent layers with an aperiodic variation of the local optic axis.

Keywords

• diffraction and gratings
• optical devices
• physical optics
• birefringent diffraction gratings
• direct ray approximation
• modal grating method