This paper introduces a simple way to measure and correct micro-displacement of piezoramic tube with intended use in atom force microscope. The X/Y micro-displacement is detected by an eddy current meter and then 100 times amplified. D/A for producing the control voltage and A/D for acquiring micro-displacement are both16 bits. The highest resolution of displacement is calculated to be 0.4nm. According to the working feature of the tube

nonlinear correction is realized by applying non-equidistant control voltage series while scanning to equidistant pixel. The non-equidistant control voltage series in the demand of different pixel resolution is obtained through interpolation based on the measured displacement-voltage relationship. By adopting the labVIEW technology the proposed system can easily adjust the scan frequency and pixel resolution for the tube. The maximum hysteresis error before and after correction are 10.1% and 0.4% respectively.