Visualization of vibrations measured with a multi‐channel optical vibration sensor.

Abstract

Displacement‐type sensor units made of optical fibers were developed to realize multi‐points measurement of vibrations with high spatial resolution. Each sensor unit has the displacement resolution of 10 nm within the dynamic range of more than 90 dB, the frequency bandwidth of up to 80 kHz. Up to 64 sensor units can be arrayed as a multi‐channel sensor head, with the minimum gap between sensor units of 4 mm. It means that the spatial resolution for the multi‐points measurement is 4 mm. The calibrating method with the measuring object was developed to realize accurate measurements. During the calibration phase, the object is kept stand‐still, and only the sensor head moves by the linear actuator. Thus, the calibration data can be obtained just before the measurement. Several arrangements of the sensor system is available depending on the object to be measured, such as line vibration, surface vibration, and the 3D movement of small object. The developed system has been used for the measurement of the actuators for vibratory microinjection and the measurement of artificial heart valves. Those results showed the advantage of the system. [This study has been supported by JSPS under the Grants‐in‐Aid for Scientific Research, Nos. 14550427 and 16560369.]