Research on 3D Surface Micro Topography Reconstruction and Mosaic from Multifocus Microscopic Image Sequences

Focus variation measurement (FVM), an optical contact-free method, has deep scientific research and application value for precision engineering, micro-manufacturing, quality inspection, biotechnology, clinical medicine and other fields. In order to reproduce a large-scale 3D surface micro topography and to realize the automatic measurement of the characteristic parameters of an object. The 3D model construction and mosaic (stitching) algorithm are excavated and studied based on 2D multifocus image sequence. In the research of 3D model reconstruction, a better focus measure is proposed based on the sum of the modified Laplacian (SML), which considers the relationship between the pixel and its diagonal direction pixels. And the 3D reconstruction models mosaic are guided by the mosaic of the 2D fused images for the reason that the pixels of the 2D fused image correspond to the depth points of the 3D reconstruction model. In order to verify the feasibility of the above methods, a comparative experiment is conducted on the standard triangular block model reconstruction with the SML and the proposed algorithm, which verifies the superiority of the proposed algorithm. Then, the two 3D models of the standard triangular block with overlapping parts are stitched and extracted the angle value. By comparing with the standard values, these angle values of 3D stitched model are within the standard value range, which verifies the feasibility of the stitching algorithm.