High resolution, high sensitivity moire method

Based on geometric moire method, moire interferometry and microscopic moire interferometry, a high spatial resolution and high sensitivity geometric m icroscopic moire method is presented. Geometric micron-moire patterns are p roduced by the superposition of two high frequency gratings through a micro scope system. Compared with other grating-based photo-mechanics: methods, m icroscopic moire method could provide whole-field moire patterns of both hi gh spatial resolution and high sensitivity. The frequency of specimen and r eference gratings used in this method can be from 1 line/mm to 10000 lines/ mm. Additionally, a 4F optical filter system is used to enhance the contras t of microscopic moire:patterns effectively.