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In this work we explore the use of infrared deflectometry in the case of dynamic vibration measurements. This work also aims to provide a comparison of the performances and implementations of visible and infrared deflectometry with measurements conducted on a laboratory test case, a cantilever aluminium beam under impact excitation. The results obtained show that both visible and infrared deflectometry enable measurements with different time and space resolutions, and that infrared deflectometry can be effectively used to perform full-field vibration measurements on an unprepared surface. It could be simply summarized that both techniques have interesting features, and what is earned with one of these techniques is lost on the other. In fact, even if the cameras used for visible and infrared deflectometry techniques have different technical features that directly influence reachable time and space scales, a key advantage is that established methods and algorithms for images post-processing are identical between visible and infrared deflectometry. This practically broadens the range of materials and surfaces that can be tested using the deflectometry technique. The extension of this technique to curved structures is also under consideration, which should provide another additional support to a greater use of deflectometry. With the increasing performance of visible and infrared high-speed cameras combined with their decreasing cost, the measurement of space- and time-resolved experimental data using the non-contact optical deflectometry techniques opens interesting perspectives.
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