Abstract: An integrated approach for micro-motion measurement that incorporates robust multiscale motion estimation algorithm into the computer microvision is presented. A robust multiscale motion estimation algorithm for micro-motion measurement is proposed. In this algorithm, according to the different properties of filters, motion at each level of the pyramid is estimated using different gradient filters. This hierarchical estimation technique can not only improve the measurement accuracy, but also accelerate the measurement speed. The composition of computer microvision measurement system is analyzed, and the designed microvision measurement system is calibrated to measure micro-motion. Taking the precision positioning stage as measurement objects, the in-plane micro-motions of the precision positioning stage are measured by using the proposed combined approach. The maximal bias of this new approach reaches 12.5 nm for motions near 2 000 nm. Experimental results show that the new combined method can measure the in-plane micro-motions with high accuracy.

Key words: Computer micro-vision, Micro-motion measurement, Multiscale, Precision positioning stage, Robust