Colorimetric property of guest-host liquid crystal displays

A bright reflective LCD without a backlight is a key device for portable information systems. The guest-host LCDs use the absorption anisotropy effect of dichroic dyes and have a wide viewing angle cone. The GH-LCD does not need complicated designs of optical compensation in birefringence or optical rotatory power modes. One of the applications of GH-LCDs is a black and white display which works as a light shutter of a full color reflective display with micro-color filters. It is necessary to mix dyes for an achromatic display. The Newton-Raphson method is useful for the calculation of optimum dye concentrations in order to display the designed color. In this work, the judgement of the calculated results is discussed. As a result, the calculated result with Newton-Raphson method is quickly and easily evaluated. The process gives us a helpful guideline in the fabrication of the reflective color LCDs and it is expected that the precise color matching improves the quality of LCDs.