In order to solve the problem of low precision in calibration and measurement of large size optical measuring instruments, mask, and other two-dimensional grid standards, a large size(1m × 1m) plane coordinate measuring method based on multi-axis laser interferometer is studied. Use a cube-corner prism as a reflector. Using a fixed bridge measuring machine structure, the co-planar motion is disassembled into independent X-axis movable table motion and Y-directional slider motion on the beam. Geometrical error modeling analysis is carried out on the measuring machine, and optical path spectral layout of multi-axis laser interferometry is studied. In order to monitor the deflection of the X-direction moving platform in real time, use two-channel laser interference to measure the length in the X-direction and a single-channel measurement of the Y-direction slider movement. Finally, a laser interferometry model with large plane coordinates is proposed and a motion simulation analysis is carried out for the deviation of X-axis mobile platform around Z axis, to verify the validity and necessity of real-time monitoring compensation error of double optical path for plane coordinates measurement.
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