METHOD TO MONITOR FIELD OF VIBRATIONS AND DEVICE FOR ITS REALISATION Russian patent published in 2015 - IPC G01D5/353 

FIELD: measurement equipment.

SUBSTANCE: optic fibre is placed in mechanical connection with a monitored object, a laser pulse is generated and introduced into the fibre. Photodetection of optical radiation scattered in inverse direction is carried out with production of a reflectogram. Information is extracted about impact at the fibre from the harmonics phase with frequency equal to difference of frequencies contained in the reflectogram. The device realising the method comprises a single-mode optic fibre, a pulse laser connected to the fibre via the serially installed and connected to each other a phase modulator and a splitter. A unit to receive and process radiation scattered in inverse direction is made in the form of a calculator connected to the splitter via serially installed and connected to each other an analogue-digital converter, a phase detector and a photodetector. A driver is connected to the phase modulator and synchronised with the pulse laser.

EFFECT: reduced probability of false actuations during detection of vibration effects or increased probability of proper detection of such effects.

8 cl, 2 dwg