A novel dynamic interferometric measurement method based on liquid level reference

Dynamic optical interferometric measurement method directly uses the liquid level as the reference surface, which immerses the tested object in liquid, and the interferograms are generated based on the optical path difference between the surfaces of the liquid and the object. The phase shift is realized by adjusting the incident angle of the laser with a rotation reflector. A generalized inhomogeneous phase shift algorithm is developed to suppress the micro-vibration of the liquid surface by the iterative least squares method combined with a confidence matrix. The high performance of the proposed method has been well verified in simulation and experiment. (c) 2024 Published by Elsevier Ltd on behalf of CIRP.