Apparatus for producing porous preforms for optical fibers

Abstract From the Canadian patent

An apparatus for the production of a porous preform of SiO2 used in the manufacture of optical fiber wherein damage to the preform caused by falling clusters of SiO2 or GeO2 formed on the wall of the deposition chamber is eliminated. In accordance with the invention a conductive shielding layer is provided inside the wall defining the deposition chamber. This shielding layer cancels an electrostatic field produced on the wall by charging, therefore preventing the adherence of fine particles thereto.