Extending the field of view of KDP electrooptic modulators

The use of KDP as a polarization rotator has been limited to small field of view instruments. To investigate this limitation, the index ellipsoid is used to describe the optical properties of KDP and to calculate the retardance and fast axis as a function of the angle of incidence and voltage. Computed converging light patterns are then compared with observed intensity patterns formed by KDP. Finally, computed intensity patterns are used to demonstrate how the field of view of KDP can be increased when properly aligned with a positive uniaxial crystal.