1. School of Physics and Electronic-information Engineering, Xiaogan University, Xiaogan, HuBei 432100, China
2. Opto-electric Information School, University of Electronic Science and Technology, Chendu, Sichuan 610054,China
Abstract：In order to realize the fast automatic PCB drill inspection, a fast arithmetic of image registration between standard PCB and testing PCB is proposed. The basic process of the image algorithm and the system structure are introduced. The process of registration is mainly consisted of approximate registration and accurate registration. Edge extraction and Hough transformation are used to obtain 4 corners coordinate of PCB firstly; the coordinates of location hole of the testing PCB can be obtained after approximate registration; the coordinates of circle center of location hole between the testing PCB and standard PCB are used to process accurate registration. Experience shows the method greatly improved the accuracy of image registration. The speed of the arithmetic also meets the needs of the real time process.
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2011, Vol. 32 
