Optical Measurements of Thermotropic Liquid Crystals

Tawfik A. El-Dessouki, Mohammed Roushdy, Nabil I. Hendawy, Magdi M. Naoum, Ayman A. Zaki

Chemistry Department, Faculty of Science, Cairo University, Giza, Egypt.
Physics Department, Faculty of Science, Ain Shams University, Cairo, Egypt.
Physics Department, Faculty of Science, Benha University, Benha, Egypt.
Physics Department, Faculty of Science, Cairo University, Giza, Egypt.

DOI: 10.4236/jmp.2013.41008                

Abstract

In this work, an experimental approach was used for measuring birefringence of thermotropic liquid crystal materials at different wavelengths in the visible region by using speckle interferometry. Also the values of the refractive indices were measured for these thermotropic liquid crystal materials in isotropic and liquid crystal phases at different wave-lengths. Temperature dependency of the refractive indices for each LC sample at certain wavelengths was investigated in the isotropic and in LC phases.

Keywords

Thermotropic Liquid Crystal; Interference; Birefringence; Speckle Photography

Conflicts of Interest

The authors declare no conflicts of interest.

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