Daily checking and calibrating method of length measuring machine

摘要

A daily checking and calibrating method includes the following steps. Step (1) is for detecting a state of the length measuring machine at a predetermined daily check time. Step (2) is for stopping the transportation of substrates upon determining the length measuring machine is in an idle state. Step (3) is for measuring coordinates of positioning marks on a substrate-carrying platform to generate a measured data file and comparing the measured coordinates of the positioning marks with predetermined coordinates. Step (4) is for automatically calculating a calibration value when a difference between the measured coordinates of the positioning marks and the predetermined coordinates is smaller than a predetermined value and updating the calibration value to a coordinate parameter file to complete automatic calibration. Otherwise, an alarm is activated. Step (5) is for determining follow-up measures when the difference between the measured coordinates of the positioning marks and the predetermined coordinates is larger than the predetermined value.