Investigation on birefringence property in uniaxial crystal (Ca0.28Ba0.72)0.75(Sr0.60Ba0.40)Nb2O6

The birefringence of (Ca0.28Ba0.72)0.75(Sr0.60Ba0.40)Nb2O6 crystal is measured basing on polarization- extinction method and conoscopic interference method. Experimental results show that the birefringence in this crystal is up to 10-5, the natural birefringence in this crystal is (no -ne) = 5.89 x 10-5 with the He-Ne laser wavelength at 632.8nm and the birefringence grads with wavelength at 532nm is 5.68 x 10-5, which indicate the good optical homogeneity of this crystal. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)