arrangement for a clear representation of images against a dark background

摘要

A display device for displaying bright images on a dark background, which device includes a liquid crystal cell having a liquid crystal layer with switchable zones between at least two optical states, a light trap in the form of a body exhibiting fluorescent particles and having light emergent windows disposed behind each of the switchable zones in the direction of observation, characterized with the liquid crystal layer containing at least one pleochroic dye. The dye in the liquid crystal layer acting by itself or in conjunction with a polarizer can block passage of the fluorescent light during one optical state of the layer and enable passage of the light during the other state.