An experimental study on digital nano-moire method

A digital nano-moire method for measuring nanometer-deformation is proposed. In measurement, periodic crystal lattices of crystal materials and atoms structure of the reconstructed surface of some PCC transition and noble metals are acted as specimen gratings, whose pitches are up to nanometer and sub-nanometer. Sine digital grating (computer generated grating) is acted as reference grating. The formation mechanism of digital nano-moire fringe and the design project of sine digital grating are discussed. In addition, the displacement and strain measurement principle, phase shifting technique and multiplication method of fringe are presented.