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

Abstract The birefringence of (Ca 0.28 Ba 0.72 ) 0.75 (Sr 0.60 Ba 0.40 )Nb 2 O 6 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 ( n o ‐ n e ) = 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)