| 摘要 |
<p>A zone plate for focusing microwave energy is provided comprising a plurality of reflective portions (14a-d) corresponding to zones of said zone plate, each reflective portion reflecting energy lambda/P out of phase with respect to adjacent reflective portions, where lambda is the wavelength of the energy. The reflective portions (14a-d) are positioned in P parallel planes (10-13) mounted on low dielectric loss sheets and separated by a distance of lambda/2P such that energy reflected from the reflective portions constructively interfere at a focus of the zone plate. Also a method and apparatus for the manufacture of such a zone plate is disclosed.</p> |
