In view of the features of display panel position of SMPDP, a precise positioning device was established using computer vision technology. This device based on industrial control computer can achieve high-accuracy position detection and full automatic precision plane alignment using CCD signals , so that it could achieve automatic precision positioning of front substratum, shadow mask and rear substratum. The algorithms such as fast image edge detection, character extraction and positioning control strategy are proposed to reduce the time of image processing and improve the detection accuracy. A series of anti-interference step in the hardware and software of the device effectively improve positioning accuracy and reliability of the device. The experimental result shows the device can perform positioning accuracy of ±5μm. The approaches are of high value for accelerating the industrialization ofSMPDP.