Furnace chemical vapor deposition (FCVD) method for special optical fibers fabrication

Abstract

The features of the Furnace Chemical Vapor Deposition (FCVD) method of manufacturing preforms for special optical fibers are considered. It is shown that misalignment of substrate silica tube and furnace hole axes has a negative effect on the quality of fabricated preforms, leading to angular and radial asymmetry of the refractive index profile. Ways of getting rid of this and other disadvantages of the FCVD method are described. Some advantages of the FCVD method over the MCVD method are shown. It was demonstrated that the FCVD method, despite some drawbacks, allows to manufacture high-quality fiber preforms with good symmetry of the refractive index profile, and thus it is promising for fabrication of dispersion, dispersion varying and active fibers.

Identification of Nanocrystalline Inclusions in Bismuth-Doped Silica Fibers and Preforms

“…Bismuth-doped fiber preforms were fabricated by modified chemical vapor deposition (MCVD), furnace chemical vapor deposition (FCVD) (Malinin et al, 2011), and powder-in-tube methods. All preforms were made using Heraeus Suprasil F300 silica substrate tubes (GmbH, Hanau, Germany).…”

“…In this paper, we apply a number of measuring techniques to investigate the spatial distribution of chemical elements and nanocrystalline inclusions in Bi-doped fibers and preforms, namely (1) microanalysis based on electron microscopy, (2) transmission electron microscopy (TEM), and (3) diffraction methods (X-ray and electron diffraction). deposition (FCVD) (Malinin et al, 2011), and powderin-tube methods. All preforms were made using Heraeus Suprasil F300 silica substrate tubes (GmbH, Hanau, Germany).…”

Optical properties of IR-emitting centres in Pb-doped silica fibres

“…A Pb-doped fibre preform, free of other dopants, was fabricated by the furnace chemical vapour deposition (FCVD) process [23,24] (a modification of MCVD that employs a movable electric furnace, instead of an oxygen - hydrogen burner, to heat a section of a silica substrate tube). A porous layer of pure SiO 2 was deposited onto the inner surface of a silica substrate tube and then doped through impregnation with a Pb salt solution.…”

Improving the Efficiency of "Jacketing" by Taking Into Account the Specifics of Applied Equipment and Prefabrications Based on Machine Learning Methods

“…Jacketing was especially intensively developed in the 80-90s of the twentieth century [1]. Currently, the most popular fiber production methods are fiber optic production methods, the parameters of which allow to successfully scaling optical fiber, such as OVD, VAD [2]. However, in the tasks of precise adjustment of the output diameter of the workpiece to the requirements of the design documentation, the technology of jacketing has no analogs [3].…”