Surface profile measurement based on continuous wavelet transform in line-scan dispersive interferometry

This paper presents a signal processing method based on continuous wavelet transform in our line-scan dispersive interferometric system. Our method enables us to extract phase information from the spectrum by applying continuous wavelet transform, which is more effective and reliable in analyzing non-stationary signal compared with FT transform. Experimental results obtained by measuring a step standard with a height of 1.806 mu m reveal that this method has high accuracy and a good performance over noise resistance, which makes it suitable for complicated in-line measurement condition.