Optical Properties of Planar Cholesteric Textures

The following are the most characteristic features of the planar textures of cholesteric liquid crystals  

FIGURE 6.4. Schematic representation of wavelength dependence of (a) optical rotatory power and (b) circular dichroism (reflection) in a planar cholesteric mixture. 

The opposite circular polarization R2) is transmitted without variation. 

The simplest theoretical model considers the optical properties of the cholesteric helix under the following assumptions  

we are now interested in the case of Bragg reflection, or more accurately, we want to establish why only one diffraction maximum of selective reflection (Fig. 6.4(b)) is observed, in experiments with the normal incidence of light, on the planar texture of the cholesteric liquid crystal, 

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