Straightness measurement system, displacement sensor calibration method, and straightness measurement method

摘要

PROBLEM TO BE SOLVED: To provide a straightness measurement system capable of suppressing a decrease in straightness measurement accuracy. A sensing unit includes three displacement sensors. The calibration reference device has a calibration reference plane. When the calibration reference planes are opposed to the three displacement sensors, the measured points of the three displacement sensors are arranged side by side in the first direction on the surface of the calibration reference planes, and the three displacement sensors are the calibration reference planes. Measure the displacement in the height direction of. When the calibration reference planes are opposed to the three displacement sensors, the tilting mechanism tilts one of the calibration reference plane and the sensing unit in the first direction with respect to the other. The processing device acquires the measured values of the three displacement sensors in a plurality of states in which the tilt angles of the calibration reference planes with respect to the sensing unit are different, and the three displacements are based on the tilt angle and the measured values for each tilt angle. The amount of displacement between the relative positional relationship of the measured point of the sensor with respect to the first direction and the specified relative positional relationship is measured. [Selection diagram] FIG. 7