METHOD FOR MANUFACTURING OPTICAL FIBER PREFORMS FROM QUARTZ SUPPORT TUBES WITH THE PRESENCE OF VOLUMETRIC DEFECTS (VARIANTS) Russian patent published in 2023 - IPC C03B37/00 

FIELD: optical fiber production.

SUBSTANCE: method for manufacturing an optical fiber preform from quartz support tubes with the presence of volumetric defects (variants) is claimed. The invention relates to fiber optics. The method according to the first variant includes the manufacture of the optical part of the preform by chemical internal vapor phase deposition (MCVD), or by chemical vapor phase deposition using a furnace (FCVD), or by plasma internal deposition from the gas phase (PCVD) with a modified proportion between the diameter of the shell and the core, in which for further complete etching of the quartz support tube in in a solution of hydrofluoric acid, after deposition of all layers of glass and the procedure of “collapsing” the workpiece, the diameter of the core is reduced by the value X, which is determined by the formula: X=D tube/K, where D tube is the thickness of the quartz support tube, K is the proportion between the shell and the core, calculated by the formula: K=D geometric cladding/D core, where D geometric cladding is the diameter of the geometric shell area of the preform, D core is the diameter of the core area of the preform. By the method for the second variant, after the manufacture of the optical part of the preform by the MCVD, or FCVD, or PCVD method, the complete etching of the quartz support tube in a solution of hydrofluoric acid is additionally carried out, after the deposition of all layers of glass and the procedure of “collapsing” the workpiece, as an intermediate step before the process of external deposition from the gas phase (OVD), or the process of jacketing, or by the process of fusing a rod blank in the center of a quartz pipe filled with quartz sand (”SAND”).

EFFECT: improvement in the quality of optical preforms made with the help of quartz support tubes in the presence of a significant number of volumetric defects located at an arbitrary depth.

2 cl, 3 dwg