Patent ID: 7539586

Claim:
A correction method for correcting a measurement error included in data obtained by tracing the surface to be measured of a work in a measurement axis direction by using a tip of a stylus, the measurement error being a measurement error due to a vertical movement error of the stylus displaced following the surface to be measured of the work, and the vertical movement error being a displacement in a translation axis direction value according to a height detection axis direction value of the tip position in a vertical movement error correction plane specified by the height detection axis and a translation axis, the translation axis being perpendicular to the height detection axis, wherein the correction method comprises: a calibration measurement step of obtaining calibration measurement data including the displacement information of the translation axis direction value corresponding to the height detection axis direction value of the stylus by moving the stylus; and a correction parameter setting step of determining a vertical movement error correction parameter value best suited for correcting the measurement error due to the vertical movement error of the stylus based on the displacement information of the stylus included in the calibration measurement data obtained in the calibration measurement step; and wherein a measurement range in the height detection axis direction is divided in advance into a predetermined number of regions, and wherein in the correction parameter setting step, the optimal value of the vertical movement error correction parameter is determined in each of the divided regions.