Abstract:Taking account of the problems that are labor-intensive,inefficient and poor-precision during the measurement of standard steel tape, working steel tape,straight steel ruler and other linear scales, automatic standard device of image type steel tape and ruler are developed based on automatic focusing machine vision technology, and high precision grating and motion control technology are employed. The devices consisted of automatic standard devices of image type steel tape/ruler and working steel tape, and the two devices shared one marble platform and outer cover, while the control system and other mechanical structure system are independent. Full automatization and high accurate measurement are achieved through stable of marble platform,automatic retractable steel tape rotating structure and accurate auto focus machine vision technology. Due to easy operation with intuitionistic results, the devices have a great value of usage and broader marketing perspective