Luminance and chrominance parameters through image analysis in ferroelectric liquid crystals

Abstract

ABSTRACT In this paper, luminance and chrominance characteristics of Chiral Ferro electric liquid crystals (FLCs): (S)-(-)-2-methylbutyl 4’-(4”-n-alkanoyloxybenzoyloxy) biphenyl-4-carboxylates (S-MB-nB-BC) where n = 16 and 18, are investigated. In optical applications of liquid crystal material, luminance and chrominance are the important characteristics and provide the information about the usage of material especially in displays. Here, ferroelectric liquid crystals' display properties based on their characteristics of luminance and chrominance are investigated using the image analysis technique. Optical anisotropy properties of the ferroelectric liquid crystal material are also computed since birefringence is an important parameter of liquid crystal material in all applications. Therefore, this investigation involves the measurement of luminance properties: luminance uniformity, luminance coefficient, luminance distribution and contrast sensitivity; and chrominance properties: chromacity coordinates, colour histogram and colour difference and optical anisotropic properties: birefringence and transient transmission. On the MATLAB platform, these properties are computed from the grey-level intensity values of the textures as a function of temperature and wavelength (red, green and blue) since chrominance and optical anisotropy are wavelength-dependent.