Resonance, non–isothermal, microwave plasmochemical systems for the
special silica optical fibers synthesis technology
L. M. Blinov
1, Yu.V. Gulyaev
1,
V. A. Cherepenin
1,
A. P. Gerasimenko
2
1
Kotel’nikov Institute of Radio-engineering and Electronics of RAS
2
"Radio engineering institute of a name of the academician A.L. Mintz",
îpen
joint stock company
The paper is received on December 5, 2014
Abstract.
Optimal designs of microwave plasmotrons, using TE111 and TM020
modes cavities, and methods of internal and external plasmochemical deposition (PCVD
and POVD) of optical structures for special two-layer optical fiber performs,
based on F-doped and N-doped silica glass, formed in a low-pressure microwave
plasma, are presented. Outside deposition of the F-doped silica reflective
cladding on a pure silica rod (POVD–method) makes possible to produce low-cost,
flexible, radiation-resistant, high-aperture (NA ~ 0.3) multimode fibers, having
pure silica core with high diameter (more, than 1 mm). Plasmochemical deposition
of the core layer (pure, or N-doped silica glass) on the internal surface of a
thick-wall silica tube, having a wall thickness 8 ÷ 10 mm, or more, which forms
the reflective cladding (PCVD-method), makes possible to produce low-cost
special radiation-resistant single-mode optical fibers. POVD-method enables also
to deposit a protective oxynitride layer on the external surface of the
two-layer optical layer perform. Method of automatic control the resonance mode
of plasmotron working and the optimal working temperature during the deposition
of optical structures for special optical fibers performs, based on using of the
high power transistor amplifier, is also presented.
Key words:
microwave plasma, resonance, optical fiber, N-doped and F-doped silica glass.