US Patent 7612516 Measuring method and system for CNC machine

This invention discloses a method and system for measuring a CNC machine. The system comprises a platform, a driving module, a set of optical scales, and a detection module. The platform is driven by the driving module. In addition, the driving module further comprises a set of encoders. As the driving module drives the platform to move to a position by a first displacement, the encoders indicate the first displacement. The optical scales indicate a second displacement by which the platform is driven by the driving module. The detection module detects the difference between the first displacement and the second displacement.