Abstract: In order to solve the problem that the pressure point of the probe is not accurate when the horizontal displacement of the chuck of the automatic and semi-automatic probe platform is deviated,which leads to the unreliable test results and even hurts the chip and probe.According to the actual process and the traceability mechanism of the standard instrument,the drawing of standard ruler was designed,electroplated 5 μm wide gold lines on soda glass,and made into 152.4 mm×20 mm rectangular standard ruler,its measurement range of （0~150）mm.The standard ruler was calibrated whit an uncertainty of 1 μm.In the measurement range,the experimental analysis is carried out and the measurement uncertainty is evaluated.The results show that the deviation of horizontal displacement measured by standard ruler is less than 4 μm,which meets the testing requirements.

Key words: Automatic, Probe platform, Displacement, Standard ruler, Uncertainty