Study on the high frequency vibration measurement by using optical fiber sensing

In this paper, a high frequency vibration detection system of optical fiber sensing has been designed based on facet reflection principle, to satisfy the requirements of high frequency vibration measurement, including aerospace and fault diagnosis of high-speed rotating machinery, etc. The system modulates high frequency vibration signal by using the reflective intensity modulation fiber-optic sensor. The vibration signal is converted into electrical signal through photoelectric conversion and amplifying circuit, and then to deal with it in the detection unit. In this way, the vibration signal has been measured successfully. In the experiment, the maximum response frequency is 33 kHz, and 2 kHz is the minimum, the frequency measurement error is below 0.5%. Comparing with other optical methods of vibration measurement, the detection system has the wider bandwidth and higher response frequency.