This paper presents the investigation on Electric field induced optical anisotropy of the planar alignment of nematic liquid crystals: 4-n alkyl benzoic acids ( nBA, where n = 6,7,8) towards the electro optic device applications. Analysis of microscopic textures of liquid crystals under the application of DC electric field is used for this investigation. It includes the computation of optical anisotropic properties from the textures of samples. As a function DC applied field, textures of the samples in the mesophase region of constant temperature are recorded in three monochromatic image planes. Optical anisotropic properties: Normalized transmittance, Absorption coefficient, Birefringence, Kerr constant and Figure of Merit are computed from the intensities of liquid crystal textures using MATLAB software. Results obtained from this investigation shows that Nematic liquid crystal: heptyl benzoic acid (nBA where n= 7) has high value of birefringence, Kerr constant, FOM and is more suitable material for the various electro optic device applications.

Keywords : Optical Anisotropy, Nematic Liquid Crystals, Image Analysis, Fredericksz Transition And Birefringence.