Robust white light algorithm for scanning error compensation

During the measurement process of a white-light interferometer (WLI), unavoidable factors such as piezoelectric transducer (PZT) scanning errors and vibrations can result in undesirable non-uniform sampling. This, in turn, leads to such problems as increasing spikes in the topography and diminishing measurement accuracy. To robustly reconstruct the topography, we have developed an adaptive wavelet for extracting the envelope and phase. Furthermore, we have introduced a method to eliminate the effects caused by the additional phase more accurately. Through simulation experiments conducted under various noise levels and coherence lengths, we have demonstrated that our proposed method consistently outperforms the existing least squares (LSQ) approach in terms of reducing spikes, enhancing measurement accuracy, and improving computational efficiency. In practical experimental measurements, our method exhibits significantly fewer spikes and lower measurement noise.