PLASMA DEPOSITION PROCESS WITH REMOVAL OF SUBSTRATE TUBE Russian patent published in 2018 - IPC C03B37/18 

FIELD: metallurgy.

SUBSTANCE: invention relates to a method for manufacturing a precursor for a primary preform for optical fibres by means of an internal plasma deposition process. Method for manufacturing a precursor for a primary preform for optical fibres by means of an internal plasma deposition process includes the steps of providing a hollow substrate tube; creating a first plasma reaction zone having first reaction conditions in the interior of said hollow substrate tube by means of electromagnetic radiation for effecting the deposition of non-vitrified silica layers on the inner surface of said hollow substrate tube; and subsequently creating a second plasma reaction zone having second reaction conditions in the interior of said hollow substrate tube by means of electromagnetic radiation for effecting the deposition of vitrified silica layers on the non-vitrified silica layers deposited in the previous step; and removing the hollow substrate tube from the vitrified silica layers and the non-vitrified silica layers to obtain a deposited tube.

EFFECT: technical result is to provide greater flexibility in the refractive index of the final preform, eliminating the need to use high-quality substrate tubes, the ability to use non-quartz substrate tubes.

21 cl, 1 ex