摘要
A scanning white-light interferometer is built for precisely measuring phase properties of dispersive multi- layer thin film structure with the aid of the commercial spectrometer. Combining seeking optimal function for interferogram maximas with wavelet denoising algorithm, a novel time-domain algorithm is presented which enables the direct extraction of group delay and thus obtains a remarkable decrease of noise level in group delay and group delay dispersion. The apparatus shows reasonable potential for multilayer mea- surement, material characterization, displacement measurement as well as profilometry.
A scanning white-light interferometer is built for precisely measuring phase properties of dispersive multi- layer thin film structure with the aid of the commercial spectrometer. Combining seeking optimal function for interferogram maximas with wavelet denoising algorithm, a novel time-domain algorithm is presented which enables the direct extraction of group delay and thus obtains a remarkable decrease of noise level in group delay and group delay dispersion. The apparatus shows reasonable potential for multilayer mea- surement, material characterization, displacement measurement as well as profilometry.
