LUT Linearity Optimization
analysis of cyclic errors and LUT compensation down to 1 nm
Periodic nonlinearities are inherent to optical displacement measurement systems and cannot be fully avoided due to fundamental effects such as multiple reflections, non‑orthogonality, and signal processing imperfections. Even under these constraints, the IDS3010 already achieves a very low intrinsic level of periodic nonlinearities, typically on the order of only a few nanometers peak‑to‑peak and around ~5 nm p‑p or below after Automatic System Compensation. This highly adaptive compensation runs continuously during operation and minimizes nonlinearities directly at their source.
For applications with stable alignment and limited variation of working conditions, the remaining periodic nonlinearities can be further reduced using the Non‑Linearity Compensation Feature.
Before Compensation
The IDS3010 can analyze its own periodic nonlinearities at the press of a button using the built‑in estimateNonlinearities function. This allows users not only to optimize performance, but also to quantify, visualize, and validate the magnitude of existing nonlinearities in a given setup.
The analysis provides clear insight into the statistical distribution of nonlinearities and the overall residual errors present in the system, including contributions from factors such as mechanical noise.
After Compensation
Based on the analysis, the IDS can generate and apply a look-up table (LUT) for targeted compensation within a defined working range. This LUT-based approach significantly reduces local nonlinearities—often down to the level of setup noise (see black line).
Combined analysis and LUT compensation enable a deeper understanding of measurement behavior while significantly reducing measurement uncertainty and lowering overall residual errors to a much improved level.