Real-time Monitoring of Structural Vibration using Spectral-domain Optical Coherence Tomography

we report in this paper the development of a spectral-domain optical coherence vibration tomography (OCVT) using a broadband CCD-based spectrometer and a shortcoherence white light source. We demonstrate that both the vibration amplitude and frequency can be quantified, in the frequency range of 0–250 Hz, with an axial resolution of 1 m. Furthermore, the inner structure (layer thickness) of a vibrating sample can also be quantified simultaneously. The developed OCVT is non-contact and noninvasive in nature, thus is ideal for real time and in situ monitoring of low-frequency micro-vibrations that have critic impacts on many high-precision manufacturing and engineering processes.