| 摘要 |
The present invention relates to use of liquid crystal material encapsulated in a containment medium to produce a controlled colored output, for example, in response to the application, removal and variation in an electric field. In one embodiment a non-pleochroic dye is in the containment medium itself and in another embodiment the non-pleochroic dye is in the liquid crystal material itself; and in both cases the object is 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., substantially transmissive.
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