Abstract:In order to quantitatively analyze the shape, size and distribution of abrasive particles on the surface of grinding head, A surface measurement and reconstruction method based on microscopic focusing principle is proposed. Firstly, according to the principle of microscopic focusing, the method of fixed-focus plane measurement and three-dimensional reconstruction is given. Then, aiming at the key focus or defocus degree analysis in the measurement method, the focus sharpness function combining background difference, gray difference and ladder difference is deduced and constructed. And the problem of missing the best focus position or focal plane in discrete image acquisition is solved by using the normal Gaussian interpolation method, and the spatial coordinates of the corresponding points of any pixel position are given. Finally, the surface image acquisition and three-dimensional reconstruction experiments of the grinding head on the electron metallographic microscope show that the shape, size and distribution of the reconstructed surface abrasive particles are basically consistent with the actual grinding head. The maximum characteristic size error of abrasive particles can be controlled within 2 μm, and the maximum distribution error is within 3 μm, which has good accuracy and reliability.