Patent ID: 8516855

Claim:
A method for producing an optical fiber preform, comprising: forming glass soot particles by jetting and combusting a glass-forming material and a fuel gas from a burner in the presence of oxygen; depositing in a plurality. of deposition passes. a plurality of deposition layers comprised of said glass soot particles on a deposition rod having a longitudinal axis, each of said plurality of deposition layers being deposited by rotating said deposition rod about said longitudinal axis at a rotational velocity while translating said burner relative to said deposition rod in parallel to said longitudinal axis at a translation velocity; and providing said preform with a density distribution that is substantially uniform in a radial direction such that each of said plurality of deposition layers has a density between about 0.4 g/cm 3 and about 1.0 g/cm 3 , by varying at least one of said translation velocity and said rotational velocity, said varying at least one of said translation velocity and said rotational velocity occurring only between deposition passes, wherein the same translation velocity is used throughout deposition of each of the plurality of deposition layers.