Wringing deformation effects in basic length measurements by optical interferometry

摘要

The effect of wringing deformations on the result of the main types of measurements by optical interferometry is studied in some detail. The wringing bending deformations can be used to improve by 10-20 times the accuracy of length measurements of gauge blocks with nominal lengths of a few millimeters. The data on the surface deformations of steel and quartz reference plates, resulting from the writing procedure of gauge blocks to their surface, are presented. Ways of crucial reduction of the plate surface deformations are reported. Surface texture deformations, arising in the tight wringing contact, are measured to be about 2.5-3 nm for modern steel and tungsten carbide blocks. Thanks to extremely high level of their reproducibility, the surface texture deformations, practically, do not affect the accuracy of the mechanical length measurements of gauge blocks.