Polarisation-independent beam scanner using electro-optic KTN crystals

A polarisation-independent optical beam scanner that uses electro-optic KTa 1-x Nb x O 3 (KTN) crystals has been demonstrated. The polarisation dependence was compensated for by using a pair of KTN beam scanners and a half-waveplate without any degradation in the performance of either KTN beam scanner. This compensation is the result of a combination of electro-optic effects consisting of Kerr effects and elasto-optic effects via the electrostrictive and elastic strains in KTN crystals.