This paper introduces zoom microscope into the microscope positioning system to settle the contradiction between microscopepsilas visual range and depth of field. In the whole bonding application, bond targetspsila identification and orientation are the most important aspects for full-automation. Multiple scale images go through various image processing programs, and finally different bond targets are identified and positioned This measure is called ldquoglobal-coarse and local-precise orientationrdquo, with which full-automation bonding is realized. A zoom microscope based micro-positioning system was used to capture the multiple magnification images. The requirement for real-time auto-focusing for zoom microscope is proposed based on the analysis of zoom microscope model.