Dual-wavelength Phase-tilting Iteration and Local Time-shifting Least Squars for Dual-channel Dynamic White-light Inteferometry

The growing interest in microprofile measurements for advanced semiconductor manufacturing and electronic glass screens has stimulated the demand for in situ dynamic white-light interferometry. However, it is challenging to perform vibration-insensitive measurements because of the broad-spectrum interference. In this article, we report a dual-wavelength phase-tilting iteration (DPTI) algorithm and local time-shifting (LTS) least squares algorithm for dual-channel dynamic white-light interferometry to extract the vibration information and recover the tested profile, respectively. The numerical simulations and comparative experiments were conducted and have shown high accuracy and reliability of the proposed method.