Patent ID: 8332173

Claim:
A coordinate measuring instrument, comprising: a probe that has a measurement piece that moves along a surface of an object; a moving mechanism that holds the probe and effects a scanning movement of the probe; and a controller that controls the moving mechanism, the controller comprising: a displacement acquiring unit that acquires a displacement of the moving mechanism; a correction-amount calculating unit that calculates a correction amount for correcting a position error of the measurement piece caused by a deformation of the moving mechanism on account of an acceleration during the scanning movement of the probe; and a correcting unit that corrects the position error of the measurement piece based on the displacement of the moving mechanism acquired by the displacement acquiring unit and the correction amount calculated by the correction-amount calculating unit, the correction-amount calculating unit separately calculating: a translation-correction amount for correcting a translation error of the probe at a reference point on the probe; and a rotation-correction amount for correcting a rotation error of the probe generated according to a rotation angle of the probe around the reference point and a length of the probe from the reference point to the measurement piece, wherein the translation-correction amount does not depend on the length of the probe and the rotation angle of the probe.