DATA PROCESSING DEVICE OF SURFACE ROUGHNESS SHAPE MEASURING INSTRUMENT

PROBLEM TO BE SOLVED: To provide a data processing device of a surface roughness shape measuring instrument which permits high-accuracy surface roughness shape measurements by appropriately eliminating errors in a driving system moving a pickup. SOLUTION: The straightness accuracy of the shaft 18 of a driving part 12 to which a pickup 10 is secured and which moves the pickup 10 in a measuring direction affects surface roughness measurement data as error components. By measuring optical flatness in shipping, the straightness accuracy of the shaft 18 is recorded in a SRAM as correction data in advance, and the correction data recorded in the SRAM are subtracted from the measurement data during measurement, whereby the error components caused by the straightness accuracy of the shaft 18 can be appropriately eliminated from the measurement data.