| abstract |
A device and method is disclosed for manufacturing optical fiber preforms utilizing microwave plasma assisted chemical vapor deposition. Precursor gas is introduced to the face of a vertically mounted dielectric rod, and a plasma is struck by means of simultaneous excitation of an E01 type wave and an H type wave with rotating linear polarization. The silica rod is positioned so that its face is at the bottom of the tube. Precursor gas is delivered from a position below the face of the silica rod, and microwave energy, which travels through the rod to the rod face, is delivered from a source positioned above the rod. With this configuration, a uniformly dense plasma localized on the face of the rod can simultaneously deposit both a pure or doped core and a doped cladding. It is also useful for creating waveguides, preform cores for use as substrates in creating optical fiber preforms, capillaries and ceramic rods. |