Multistage Quality Control of Active Fiber Light Guides

A complex of techniques has been developed and facilities have been designed for multi-stage quality control of active optical fibers. The complex includes an experimental stand for measuring hydroxyl groups in quartz glass grains by the absorption of grains in the overtone region of stretching vibrations of O–H groups 1300–1450 nm; an apparatus for measuring the concentration of erbium ions in a blank (the method is based on measuring the intensity of the luminescence of erbium ions in the wavelength range of 1.54–1.56 µm); and an experimental reflectometer for quality control of active optical fibers. These experimental techniques together provide a flexible tool for monitoring the quality of active fibers from raw material preparation to finished fiber testing.