High-aperture optical waveguides based on fluorine-doped silica glass

The dependence of fluorine incorporation into silica glass on conditions of the optical waveguide blank manufacture using the method of modified chemical vapor deposition (MCVD) is studied. The degree of fluorine incorporation at constant consumption of a fluoridizer (SiF4) is shown to increase with an increase in the volume of deposited material. Samples of multimode optical waveguides with a core from pure silica glass and a reflective coating made of fluorine-doped silica glass with a numerical aperture of ∼0.18 are obtained. Optical losses in such optical waveguides reach 0.5 dB/km in the long-wavelength region of the spectrum.