Plasma Deposition Technology
Heraeus started to develop the Plasma Outside Deposition (POD) process in the mid-1970’s. It is a unique method to produce multimode preforms with step index profiles by cladding a core rod with an outer layer of highly fluorine doped silica glass. Plasma torches transform the reactants SiCl4, O2, and a fluorine containing gas, into layers of fluorine doped synthetic fused silica. Strong thermal gradients, combined with the high temperature plasma, allow very high fluorine concentrations to be incorporated into the fused silica network. Using this process with un-doped core rods, refractive index differences of 0.028 (equal to 1.9 %) can be achieved, creating numerical apertures in excess of 0.28, which is an unmatched feature of the POD process.
Long experience as the basis for new ideas
Heraeus has more than 30 years of experience in specialty fiber preform production and applications. We continuously improve material quality, product characteristics, process technology, and optical characterization methods. We develop new preform types for, and in cooperation with, our customers. We are able to produce these preforms with short lead times for standard as well as for customized types. Finally, our large batch processes enable cost-effective manufacturing of the highest quality preforms for price-sensitive applications.
