Two optical techniques are developed for the accurate measurement of birefringence in liquid crystals and the observation of the variation of the angle with temperature of the small angled prism used for the measurement of refractive indices in liquid crystals. It has been observed that the small variation of the angle of the prism makes a considerable variation in the birefringence. Hence, a simple technique has been developed for this measurement. The second optical setup developed works on the principle of Newton's rings and gives directly the birefringence of a liquid crystal. The development details and the preliminary results are presented and discussed in the light of the available techniques.