DEPENDENCE INVESTIGATION OF THE ANISOTROPIC SINGLE-MODE FIBER PARAMETERS ON A WINDING DIAMETER

Experimental setup has been designed that makes it possible to measure linear losses in optical fibers by the insertion loss method and h-parameter in anisotropic single-mode optical fibers by crossed polarizer method. The dependence of the single-mode anisotropic optical fiber linear optical loss and h-parameter on a winding diameter has been investigated. In the experiment, the winding diameter was changed with increment of 2.5 mm at a range of diameters from 3 to 50 mm and with increment of 0.5 mm at a range of diameters from 3 mm to 10 mm. The investigation has been carried out for the birefringent optical fibers with elliptical stressed core and GeO2 doping concentration of 4, 12 and 18 mol. %. On the base of analysis results recommendations for the allowable bending
diameter of anisotropic single mode optical fibers used in interferometer fiber-optical sensors have been made. The measured parameters are the average values for the bent portion as control of even distribution of mechanical stress and spatial orientation of the elliptical shell in the samples during the present experiment was not carried out.