New method of extremal surfaces for most efficient application of crystalline materials in electro-optic devices

New method for geometry determination of most efficient application of crystalline materials as active elements of electro-optic devices is proposed. This method is based on the analysis of properties of the extremal surfaces obtained by optimization procedure and consists in the determination of such directions of the electrical field and the wave normal that maximize the path difference for two orthogonally polarized waves, which can propagate along arbitrary direction in investigated crystal. The method of extremal surfaces was approbated in example of LiNbO₃ crystal.