Controller for surface texture measurement device and method for controlling the same

A surface texture measurement device capable of resolving errors for each entire display range, a controller for the surface texture measurement device, and a method for controlling the surface texture measurement device that includes selecting any one of the display ranges as a reference range and defining a calibration measurement value for each display range; sequentially inputting the calibration measurement values in place of the measurement values to the range amplifier corresponding to the reference range to obtain a reference display value rDATAi; inputting the calibration measurement values to the range amplifiers corresponding to each display range, then obtaining an AD-converted value ADi and a display value DATAi; computing a gain error rate ki = rDATAi / DATAi, a display resolution DIVi = DATAi / ADi, and a corrected display resolution cDIVi = DIVi × ki; and displaying the corrected display value cDIVi = DIVi × ki.