METHOD FOR CALIBRATING COORDINATE AXES SQUARENESS ERROR AND 3-DIMENSION SHAPE MEASURING DEVICE

PROBLEM TO BE SOLVED: To correct the squareness error of 3-axis coordinate axes in a short calculation time by automatically assuming a corrective parameter with easy operation, with no skilled operator. SOLUTION: A coordinate transfer matrix assuming part 13 assumes a coordinate transfer matrix so that the difference between an ellipsoid which is acquired through coordinate-transformation of an ideal spherical surface and the actual data of a reference spherical surface is minimized. A squareness error correcting part 14, using the parameter of the assumed coordinate transfer matrix, performs coordinate-transfer to the sequence of points data for an object to be measured for automatic squareness-error correction between measurement coordinate axes, resulting in precision measurement with no variation in shape measurements for an optical element such as lens and aspherical surface which is caused by operators while no labored and complicated calibration work required.