Optical Device for Measuring Small Displacements of Control Objects Surfaces with Protection from External Mechanical LoadingI. P. Miroshnichenko, I. A. Parinov, T. P. Savostina and V. P. SizovE3S Web Conf., 124 (2019) 03012DOI: https://doi.org/10.1051/e3sconf/201912403012