The mode characteristics of a planar five-layer W-lightguide with various refractive indices of the intermediate layer are investigated, based on a numerical solution of the dispersion equation. It is shown that it is easy to ensure the single-mode regime in a broad range of wavelengths, the necessary field concentration in a large-diameter lightguide core, and efficient filtering of the evanescent modes in W-lightguides by appropriately choosing the geometrical and optical parameters.
展开▼
