Viewing angle switching of tristate liquid crystal display

A tristate liquid crystal display characterized by two optically distinct dark states and one bright state has been presented. These two dark states contribute to two different viewing angles, of which one is used for wide viewing mode operation, whereas the other one for narrow viewing mode operation. Each viewing mode can be directly selected electrically from two sets of driving voltage. We demonstrate a vertically aligned nematic cell as a paradigm to explain the principle of viewing angle switching. Its appealing feature is that both the information sharing and the privacy protection are supported simultaneously on a single panel of liquid crystal display.