IMF2017

In this work, an experimental approach was used for measuring refractive indices and birefringence of LiNbO₃ singel crystal over a wide range of wavelength and temperature. We proposed a speckle photography method for the measurements. The main advantages of our method is the simplicity of optical set-up that uses a single refrence beam, thus reducing mechanical stability requirements of the set-up. Experimental results have been presented to validate the theoritical predictions. The values of refractive indices and birefringens were obtained with an acceptable degree of accuracy. Speckle photography , photo-refractive materials, refractive indices, birefringence.