Optical characteristics of a reflective guest-host liquid-crystal display with a phase compensator and no polarizing sheet

Computer modelling is used to study a reflective STN liquid-crystal guest-host display with a phase compensator and no polarizing sheet. It is shown that, by choosing the parameters of the phase plate, the spectrum of the dye, and the twist angle in the liquid-crystal (LC) structure, it is possible to simultaneously obtain high values of the reflectance and the image contrast as well as a high degree of multiplexing. It is shown that an LC structure with a twist angle of 250° is optimal from the viewpoint of the ergonomic characteristics of the display. For this LC structure, the degree of multiplexing of the display can exceed 100:1 when the reflectance in the ON state is at least 21% and the image contrast is at least 5:1 for black-and-white dye. For colored dye, the image contrast at the wavelength of the maximum absorption of the dye can reach 10:1. © 2001 The Optical Society of America.