Liquid Crystal Alignment on Microgroove Surfaces

It is well known that the main reason for liquid crystalline alignment on rubbed polymer surfaces is the anisotropic characteristics of the stretched polymer surfaces, although it is also due to microgroove structures [1]. 

2 shows the temperature dependence of the liquid crystal order parameter on microgroove surfaces with different pitches. 

For LCD production, the direction of the liquid crystalline molecular inclination relative to the alignment surface, as well as the liquid crystalline direction on 

To prevent tilt reverse disclination occurrence on microgroove surfaces, hybrid type cells with a rubbed alignment layer and a microgroove alignment layer have been proposed [7]. In Fig. 3.4.4(a), the liquid crystal configurations on 

Usually, in the case of TN and STN LCDs, small amounts of optically active compounds are added to prevent the coexistence of two kinds of twisted states. In Fig. 3.4.4(b), the left and right sides show two possible configurations in hybrid cells with liquid crystalline material containing an optically active compound. In both configurations, the liquid crystalline materials are twisted in the same sense, as determined by the optically active compound. 

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