DEVICE FOR MEASUREMENT OF LONGITUDINAL TEMPERATURE DISTRIBUTION IN POLYMER COATING OF ACTIVE WAVEGUIDES OF FIBRE LASERS AND AMPLIFIERS Russian patent published in 2017 - IPC G01K7/34 

FIELD: measuring equipment.

SUBSTANCE: invention relates to measurement equipment, in particular to measurement of temperature of fibre-optic guide polymer shell. Device includes optical fibre with dielectric polymer shell, separate sections of fibres are placed between metal coatings of capacitors. Coatings of capacitors are parallel sections of optical fibre and are adjacent to fibre on opposite sides. Capacitors are connected with separate coils or are connected to common inductance coil. Formed oscillating LC-circuits are local temperature sensors, which are included in electric circuit allowing to measure their amplitude-frequency characteristic. Since dielectric permeability in radio frequency range of polymers used in fibre optics has manifested temperature dependence, temperature of heated polymer is measured by method of radio-frequency impedance spectroscopy. Process of fibre-optic guide polymer coating temperature distribution measuring includes device calibration with uniform heating of optical fibre and measurement of dependence of resonance frequency of amplitude-frequency characteristic of each oscillatory circuit from measured homogeneous temperature. Distribution of temperature of polymer coating along length of fibre at generation or amplification of radiation in optical fibre is determined from comparison of shift of resonance frequency of each of oscillatory circuit with calibration coefficients.

EFFECT: broader functional capabilities.

4 cl, 4 dwg