| 摘要 |
<p>A millimeter-wave window (10) is constructed from a high conductivity metal plate (12). The metallic plate (12) is made transparent over a range of frequencies by perforating it with a periodic array (39) of slots (14). In one embodiment, the millimeter-wave window (10) is used in a gyrotron as the output window. In such a case, one suitable periodic array (39) of slots (14) comprises an equilateral triangular array (39') of slots (14) for operation at 95 GHz. By proper choice of the hole (14) spacing and diameter, the window (10) can be made transparent at any desired frequency. In addition to being transparent, however, the window (10) must also be vacuum tight, as the pressure inside a gyrotron is on the order of 10-9 torr. The present invention solves this problem by covering the surface of the window (10) with a thin layer (18) of a suitable dielectric material, such as fused quartz.</p> |
