Simulation-based systematic error compensation for nanoprofiler using normal vector tracing method

• The influence of the assembly error of nanoprofiler is low-order components.
• The influence of the assembly error of nanoprofiler is linear to the amount of error.
• The influences of each assembly error of nanoprofiler do not affect each other.
• The assembly error amount can be estimated after the device assembly of nanoprofiler.

We have developed a nanoprofiler that relies on the use of the normal vector. Our aim was to enable the measurement of the profile of free-form surfaces with high precision. Since the nanoprofiler does not use a reference surface, it should be capable of measuring free-form surfaces with a high degree of accuracy. Repeatability at the sub-nanometer level has been achieved. In this study, with a goal of reducing and evaluating the related uncertainty, we set out to estimate the degree of systematic error. We investigated the effect of the systematic error on the measurement results by computer simulation. Then, by comparing the measured results with those of the simulation, we estimated the systematic error.