International comparison of noise in areal surface topography measurements

Abstract An international comparison of surface topography measurement noise was carried out. The involved twelve optical instruments (focus variation instruments, confocal microscopes and coherence scanning interferometers) from six European research laboratories. purpose this to perform a practical test the ISO definition procedures for determining on variety provide good practice guidance user community quantifying, specifying interpreting noise. Despite taking steps enable an optimal by supplying specimens, where ‘best’ could be selected area clearly defined, appropriate beyond actual conditions complex, as time, speed lateral resolution were difficult establish most instruments. results that obtained were: (i) measurment N M can reliably estimated two measurements, (ii) may vary considerably between even when they have same principle, (iii) in higher than with levelled flat, (iv) ‘rms repeatability’ has little correlation determined according specification standard, lead values are more hundred times smaller.