| 摘要 |
<p>A hollow waveguide (1) has a wall (3) having plural pegs (16) thereon. The pegs (16) which project into the hollow interior of the waveguide (1) such that the waveguide (1) propagates electromagnetic waves only below a certain frequency. The surface of each of the pegs (16) is substantially free of discontinuity and concavities. The waveguide (1) may be manufactured by a moulding process.</p> |
