| 摘要 |
The present invention relates to use of liquid crystal material encapsulated in a containment medium to produce a controlled colored or multi-colored output, for example, in response to the application, removal and variation in an electric field. A non-pleochroic dye may be in the containment medium itself, in the liquid crystal material itself or both, the object of the dye being to color light. Incident light impinging on the encapsulated liquid crystal material, which is mounted on, in, or with respect to a support medium, is isotropically scattered in the absence of an electric field, and using the principle of total internal reflection (or optical interference or both) a relatively large part of the isotropically scattered light in the support medium is reflected back to illuminate the scattering liquid crystal material, which isotropically scatters such light again, thus increasing the optical path through the dyed material and, therefore, the coloring of the light traveling such increased path. Light scattered back to the viewing direction out of the support medium causes the liquid crystal material to appear relatively bright and colored as compared to the background where there is no liquid crystal material or where the liquid crystal material is in parallel alignment in field-on condition, i.e. aligned with respect to an electric field, and, thus substantially transmissive. Original incident light where there is no liquid crystal material, that light which is isotropically scattered toward the back or non-viewing side of the display and within a certain cone or solid angle, and that light passing through aligned (field-on) liquid crystal material will tend not to be totally internally reflected; such light will pass through the support medium and may be absorbed by a remote black or colored material. Light amplification type of operation according to another embodiment in which the dye is a fluorescent one that fluoresces, isotropically emitting light in response to incident light (or possibly other radiation). The non-pleochroic dye may be imbibed in the containment medium itself. Different color dyes may be placed at different areas of the encapsulated liquid crystal structure to achieve different color outputs. In the imbibing process water soluble dye is applied to the exposed surface of a water base containment medium of already encapsulated liquid crystal material. Humidity is applied, and the dye imbibes into a proximate area of the containment medium preferably going into solution therewith. Another aspect of the invention relates to the locating of different color areas of the encapsulated liquid crystal structure close together, e.g. like the color dots or pixels of a color television picture tube. Then, by selectively scanning the respective areas, e.g. applying or not, an electric field thereto, the effect of a color image similar to that of a color television picture tube may be obtained. |
