| 摘要 |
A cell composed of a polymeric layer which encapsulates a nematic liquid crystal which is self-adherent to an electrically conducting glass or plastic sandwich-like support. The cell is transparent in its natural state and becomes opaque by applying an electrical field (reverse-mode operation). The method for manufacturing a cell according to the present invention consists in dispersing, in a polymerizable organic medium, microspheres of nematic liquid crystal, forming a fluid emulsion. The emulsion is placed between two rigid or flexible glass or plastic supports which are rendered electrically conducting; then, by means of the action of a magnetic field (or other force field), the liquid crystal molecules are orientated; this also causes an impression, at the interface of the orientated liquid crystal spheres, in the dispersing organic medium. In this condition in which a magnetic field or other force field is present, the organic medium is polymerized for example by ultraviolet radiation or by heating. Once polymerization has occurred, and once the magnetic field has been removed, the liquid crystal molecules maintain their orientation, which can be altered reversibly by applying an electrical field to the conducting support. Operation is of the "reverse mode" type with high optical contrast. |
