| 摘要 |
<p>A liquid crystal cell (40) has two infra-red transparent windows (42) and liquid crystal molecules (50) in the space between. At least one of the windows (42) is a sheet of infra-red transparent, semi-insulating crystalline material, such as gallium arsenide, having an ion implanted surface region (44). The sheet (42) is annealed after ion implantation to electrically actuate the implanted ions. The sheet (42) has uniform infra-red transmission characteristics over its surface and is provided with anti-reflection layers (46 and 47). An electric potential (V) can be applied from a source (56) to the two windows (42) to establish an electric field (E) in the cell and thereby electrically orient the liquid crystal molecules (50).</p> |
