METHOD OF FABRICATING MONOMODE ACTIVE STRIP OPTICAL WAVEGUIDES FOR OPTICAL TELECOMMUNICATIONS

摘要

In order to fabricate monomode active strip opticalwaveguides for optical telecommunications, a layer ofvitreous soot is deposited on a substrate and isimpregnated with a solution of a precursor of a rare-earthdopant, and radiation with a wavelength in an absorptionband of the dopant is focused on the soot, and moved alonga trajectory corresponding to the configuration desired forthe guide, thereby forming a vitrified strip. The soot maybe pre-doped with a refractive index raising dopant, or aprecursor of such a dopant may be included in the solution.The substrate may be of a polygonal tubular cross-section,and the soot deposited on an inside surface. This enablesseveral waveguides to be formed at once, and protects thesoot layer from contamination.