A Coarse Interval Linearity-Calibration Method Involving Self-Inspection Technique for Displacement Sensors

A calibration method for displacement sensors is proposed, in which linearity errors over a calibrating range can be approximately known every coarse interval with an equal nominal output width. The method has a characteristic of a kind of the self-inspection technique in the sense that except input references corresponding to the interval, whose actual values are unknown, special references for calibration are not needed. Two kinds of electronic micrometer being taken up as objects of calibration, experiments are carried out to examine the method in a range of 300 μm under some conditions. Comparisons between experimental results by this method and other ones and an examination of calibration errors are also performed. Linearity errors obtained in all cases show good agreements within about 0.1 μm. This method is considered to have a possibility to the purpose.