DISTRIBUTED FIBRE-OPTIC SYSTEM OF VIBROACOUSTIC SIGNALS REGISTRATION Russian patent published in 2013 - IPC G01H9/00 G01D5/353 

FIELD: measurement equipment.

SUBSTANCE: registration system comprises a fibre-optic metering line on a single-mode optical fibre with an installed Fresnel or Faraday reflector at one side, and at the other side - connected to an optoelectronic unit, which comprises a laser source connected with the first input of a splitter of X-type. The first output of the splitter is connected to the specified metering line, and the second one - to a sound-insulated coil from a single-mode fibre, serially connected to a reflector on the second end. Lines produce an open double-arm circuit of a fibre Michelson interferometer, signals from which arrive from the second input/output of the splitter to a photodetector and a recorder of vibroacoustic signals. Local sensors of vibration signals are linear sections of fibre in the metering line, fixed to the vibrating surface of the object, and sensors of acoustic signals are represented by a single small-sized coil from a single-mode optical fibre or at least one multiturn element from a single-mode optical fibre.

EFFECT: increased sensitivity of measurements in a wide band of frequencies of both vibratory and acoustic signals with the help of one fibre-optic line.

11 cl, 1 dwg