High-precision grating displacement measurement system has the advantages of nanometer repetition accuracy, strong environmental adaptability, and easy expansion of dimensions. It can meet the measurement requirements of the precision manufacturing industry for the integration of meter-level measurement range, submicron-level accuracy and multi-dimensional measurement capability. It has important applications in high-end manufacturing, precision instruments and other fields. By studying the parameters of the measuring grating, the size and manufacturing accuracy of the measuring grating are improved. High-precision conical diffraction grating displacement measurement, high power subdividing steering interferometric grating displacement measurement, 品-shaped splicing large range grating displacement measurement and other technologies are proposed to achieve sub-micron measurement accuracy in hundreds of millimeter measurement range. From grating fabrication to measurement system development, theoretical analysis and technical verification are provided for improving measurement accuracy, resolution and range.