| Abstract: | A simple optical method based on refractive indices measurement for determining the tilt bias angle of liquid crystals is described. The required refractive indices no, ne and nθ are measured by (i) Abbe's refractometer and by (ii) optical wedge method. The tilt bias angle by this technique can be determined to accuracy of ± 0.2° in the high tilt angle range (20° to 40°). This method is rather simple and quick and does not require any external magnetic field and/or knowledge of other physical constant of liquid crystals, as are necessary in some of the earlier reported methods. |
