分析比较了不同孔径、不同膜厚的金属膜空芯波导与介质金属膜空芯波导在损耗、色散、耦合效率等方面的传输性质。研究表明, 较大的波导孔径与较小的介质膜厚能够获得较低的传输损耗。同时, 镀制一定厚度的介质膜, 将增大波导的单模传输范围并改善波导的色散特性。研究了高斯光源与波导的耦合效率, 通过选择合适的光源, 使高次模与波导的耦合效率远低于基模。讨论了介质膜对波导与光源之间耦合效率的影响, 以及其在传输波长接近波导尺寸时对波导电场分布的影响。

We analyze and compare the transmission characteristics of the metallic hollow waveguides and dielectric-coated metallic hollow waveguides with different diameters and dielectric layer thicknesses, in terms of attenuation, dispersion, and coupling efficiency. It is shown that a bigger diameter and a thinner dielectric layer can achieve a lower transmission loss. We can coat a dielectric layer to improve the single-mode transmission range and dispersion property. We study the coupling efficiency between a polarized Gaussian beam and the waveguides and find that coupling efficiencies of high-order mode are lower than that of the fundamental mode for a proper optical source. We discuss the influence of the dielectric layer on the coupling efficiency, and also analyze the influence of the dielectric layer on the electric field distribution when the transmission wavelength is close to the diameter of the waveguides.