White-Taylor displays

This equation was derived for an infinitely thick cholesteric layer where there is no torque exerted by the boundaries and cholesteric material has its natural pitch. However, it holds reasonably well for practical devices with large d/p ratios, and in particular for White-Taylor displays with homeotropic boundaries having no forced pitch. The threshold characteristic shows a noticeable hysteresis. The winding voltage Vnc is given by (see Fig. 16)... 

Other dichroic display types to improve the viewing angle of standard TN-cells can be found in the literature. The most popular are dichroic phase change effect displays or White-Taylor mode displays [21 ] and Heil-meier type dichroic LCDs [20, 22, 23]. 

Figure 3.15 Schematic representation of a White and Taylor guest-host liquid crystal display (GH-LCD). ...

The importance of surface orientation on the performance of guest-host displays was recognized by White and Taylor, who investigated displays having both parallel and perpendicular boundary orientations. In this section we will look more closely at the textures and electro-optical properties of guest-host layers having these two types of boundary orientation. 

D. E. White and G. N. Taylor, New absorptive mode reflective liquid-crystal display device , J. Appl Phys., 45,4718 (1974). 

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