Video-Based Interferogram Analysis for Measuring Influence of Vibration to White Light Interferometry

In this paper, we present a video-based interferogram analysis method for measuring the influence of vibration on white light interferometer in terms of undesired change in optical path difference between reference and sample arms. The measurement principle is based on the analysis of interferograms which involves tracking and converting change in interferograms to physical change in optical path difference. The method proposed uses the original sensor in interferometer for data acquisition as such no additional hardware is required. Such an approach ensures that the properties of interferometer such as the bandwidth of sensor are considered and the vibration pattern recorded is close to the effective influence of vibration. With our method, the influence of vibration on white light interferometer and the performance of vibration isolation system can be objectively quantified and measured.