摘要
A type of combined optical fiber interferometric acoustic emission sensor is proposed. The sensor can be independent on the laser source and make light interference by matching the lengths of two arms,so it can be used to monitor the health of large structure. Theoretical analyses indicate that the system can be equivalent to the Michelson interferometer with two optical fiber loop reflectors,and its sensitivity has been remarkably increased because of the decrease of the losses of light energy. PZT is powered by DC regulator to control the operating point of the system,so the system can accurately detect feeble vibration which is generated by ultrasonic waves propagating on the surface of solid. The amplitude and the frequency of feeble vibration signal are obtained by detecting the output light intensity of interferometer and using Fourier transform technique. The results indicate that the system can be used to detect the acoustic emission signals by the frequency characteristics.
A type of combined optical fiber interferometric acoustic emission sensor is proposed. The sensor can be independent on the laser source and make light interference by matching the lengths of two arms, so it can be used to monitor the health of large structure. Theoretical analyses indicate that the system can be equivalent to the Michelson interferometer with two optical fiber loop reflectors, and its sensitivity has been remarkably increased because of the decrease of the losses of light energy. PZT is powered by DC regulator to control the operating point of the system, so the system can accurately detect feeble vibration which is generated by ultrasonic waves propagating on the surface of solid. The amplitude and the fre- quency of feeble vibration signal are obtained by detecting the output light intensity of interferometer and using Fourier transform technique. The results indicate that the system can be used to detect the acoustic emission signals by the fre-quency characteristics.
基金
the Fundamental Research Foundation of Harbin Engineering University, (grant number HEUF 04017)
关键词
光纤
干涉仪
传感器
声音
散射
Acoustic emissions
Acoustics
Electric network analysis
Fiber optics
Fibers
Fourier transforms
Geodetic satellites
Interferometers
Interferometry
Lattice vibrations
Light sources
Michelson interferometers
Optical fibers
Optical in
Acoustic emission sensors
Acoustic Emission signals
Fiber loop reflectors
Fourier
Frequency characteristics
Interferometric sensors
Laser sources
Light energy
Light intensities
Operating points
Optical
Vibration signals
