Photoluminescent liquid crystal displays use a liquid crystal to modulate the intensity of ultraviolet light incident on visible emissive phosphors. In order to gain optimum performance from the liquid crystal in such a device, the activating light must cover a narrow spectral bandwidth very near to the visible (violet) region of the spectrum. Calcium sulphate europium phosphor offers an emission spectrum closely matching these requirements and has been incorporated inside low pressure mercury cold cathode fluorescent lamps. These have been used to backlight a photoluminescent liquid crystal display demonstrator.

No abstract

No abstract

Photoluminescent liquid crystal displays (PLLCDs)use an LCD to modulate the intensity of activating (ultra violet) light incident upon visible emissive phosphors. The UV backlight and the visible emitting front screen phosphors must meet specific requirements in order to achieve optimum performance. This paper identifies phosphor materials that meet the requirements for PLLCD.