A liquid crystal display screen having a liquid crystal layer disposed between a pair of carrier plates to form a liquid crystal cell characterized in a plurality of electrode layers disposed between the carrier plates with adjacent electrode layers being separated by an insulating layer and selected electrode layers being in the shape of characters or digits and being energized to form displays of different characters or digits. In one embodiment, a digit electrode layer is applied on opposite faces of the liquid crystal layer and a continuous electrode is separated by an insulating layer from each of the additional electrode layers. In a second embodiment, the liquid crystal layer is disposed between a continuous electrode layer and more than two digit electrode layers with the outermost digit electrode layer being continuous whereas the inner digit electrodes have interrupted conducting surfaces. In the third embodiment, a color filter such as a three-color triplet having the colors arranged in strips is disposed between the carrier plates, the continuous electrode is formed by three electrode layers separated by insulating layers with each layer having strips of electrodes overlying the strips of a specific color so by selecting the energizing of various electrodes, a character of one color can be produced.
This invention provides a nematic liquid crystal display device for displaying a first information in the absence of any control voltage and substituting for that another information, or successively several other informations, by application of a control voltage. Several embodiments are described, in which either rotatory polarization effect in twisted structures or dynamic scattering effect are used.
The present invention includes a multi-electrode structure including a counterelectrode, a display electrode in registry with the counterelectrode and finally an intermediately positioned apertured background electrode. Display material is contained between the counterelectrode and the background electrode. Depending upon the electric field conditions existing between the various electrodes, a display image may be created with a first dark-light contrast relationship relative to a background. An appropriate driving circuit is capable of changing the field relationship between the electrodes so that a reverse contrast relationship appears between a displayed image and its background.
An electro-optical display device for representation of an item of information such as digits, the display device including a front and rear plate spaced apart to form a cavity for receiving a switchable medium, the front plate on a surface facing the medium being provided with at least one segmented electrode having segments and the rear plate on a surface facing the front plate and the medium being provided with a rear electrode assembly for each segmented electrode, the segments of the segmented electrode and the rear electrode assembly being energized to switch the optical properties in the medium characterized by front control electrodes being disposed on the front plate and electrically connected with selected one of the segments of each segmented electrode and a back control electrode disposed on the rear plate overlying the front control electrode so that an indication is made by one of the front control electrodes and the back control electrodes when the associated segment should be energized.
A liquid crystal light valve projection type image display apparatus comprises an electro-optic element and a Schlieren optical system. The electro-optic element has a liquid crystal layer having a dielectric and optical anisotropy. An electric field having a spatial intensity distribution according to an image signal is applied to said liquid crystal at a spatial period, so that a spatially phase-modulated phase diffraction grating is formed in the liquid crystal layer. Thus, a projected image in enlarged form is obtained. The fact that the electric field with a spatial period is applied to the liquid crystal leads to a constant light diffraction angle, and the modulation of the diffraction light intensity in the applied electric field enables an image corresponding to the input image signal to be projected at high light utilization.
A liquid crystal display system and cell configuration is disclosed. The element has a first substrate, having a first substrate electrode and a second substrate having a second substrate electrode approximately parallel to the first substrate. In between the two substrates is sandwiched a cholesteric liquid crystalline material. The pitch of the cholesteric material can be controlled by at least two interdigitized electrodes, electrically separated from each other, arranged on the second substrate.
