Development of Two-Dimensional Scanning Moire Method for Full-Field Micron/Nano-Scale Deformation Measurement

摘要

A two-dimensional (2D) scanning moire method was proposed to measure the micronano-scale deformation distributions in two dimensions using a single moire pattern under a laser scanning microscope. The 2D scanning moire pattern in a large view field (width is 500～2000 times the grating pitch) comes from the interference between a cross specimen grating and the 2D laser scanning dots which serve as the reference grating. The 2D scanning moire fringes can be separated to two groups of parallel one-dimensional moire fringes in two directions using complex Fourier transform. The full-field micronano-scale deformation distributions in the x and the y directions are measureable from the corresponding parallel moire fringes, respectively. Consequently, the 2D displacement and strain distributions can be determined using a single 2D moire pattern, instead of two moire patterns in two directions. The proposed method possesses the advantages of time saving, large view field, non-destruction, and high accuracy for two-dimensional deformation measurement of various materials evaluation.