New method for the measurement of aeroengine blade edge

A new high accuracy method for blade edge measurement based on light-section principle is proposed. The section image is captured by CCD and processed by computer. The structure of the system and mathematic model are introduced, and the method for decreasing the influence of stray light is proposed. the algorithm of edge extracting based on direction estimating and the arc least square fitting methods are discussed, the experiment results are given at the end of the paper.