What is the linearity of the Non-contact Thickness/ Displacement Meter specification?
Linearity shows the maximum error range of the measurement value according to the true value of the gap.
In the case of displacement measuring, the accuracy is the linearity specification. For example, when you are using the VE-1520 as a sensor, full scale (F.S) is 1500 µm, so the accuracy is ±2.25 µm.
The maximum error of the thickness measurement specification is twice as large as the linearity specification, because it measures the gap between two sensors and calculates the thickness with an operation. Generally, the reference thickness range is the master piece and calibrating the target measurement object in the thickness measurement. Measurement error is affected by a gap difference, so the master piece calibration is effective to prevent measurement error. In order to perform the error smaller than the specification, prepare a master piece for each and every type of measurement work, minimize the thickness gap between the master piece and measurement work, in addition to minimize a gap of the position for work during the measurement.
Revised:2011/04/18