This paper presents a deep-learning-based algorithm dedicated to the processing of speckle noise in phase measurement from holography. The deep learning architecture consists in a pre-trained residual convolution neural network, initially devoted to de-noising of natural images. In order to adapt the network to de-noise phase maps, a database is constituted by a set of noise-free and noisy-phase maps corresponding to realistic noise conditions (non-Gaussian, non-stationary, controlled speckle size). The algorithm is qualified according to quantitative metrics such as the phase error, the error method, the Qindex and the computation time. This paper demonstrates that the proposed de-noising algorithm yields stateof-the-art results in terms of phase error and error method. In addition, the processing efficiency in term of computation time appeared to be better. So, de-noising of phase maps using such deep-learning-based approach is expected to yield very promising results in optical metrology. Application of the method to the characterization of vibrations over surface about 400cm2 is presented when dealing with vibration amplitude of 20nm at 17kHz recorded at 100kHz by a high speed in-line Fresnel configuration.
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