"JOURNAL OF RADIO ELECTRONICS"  N 12, 2014

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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.