White light microscopic interference morphology reconstruction method based on mixing interference fringe

The present invention provides a white light microscopic interference morphology reconstruction method based on a mixing interference fringe. A Mirau-type white light interferometry optical system is employed, a piezoelectric ceramics mobile station is employed to perform precision control of the vertical scanning movement of an interference objective, and a series of collected white light microscopy interferograms are stored. The collected interference grey-scale map is converted to a light intensity graph, a normalization modulation degree graph corresponding to a single-frame interference image is obtained through the frequency domain filtering and the base frequency signal extraction algorithm, and aiming at each independent vertical scanning position, a mixing interference image is obtained through the multiple of the same pixel point light intensity value and the corresponding modulation degree numerical value. A series of mixing interference images are obtained through vertical scanning, and the height information of each pixel point of a detected object is obtained through searching the mixing interference extreme value and the corresponding scanning displacement thereof to realize the three-dimensional morphology reconstruction of the object. The white light microscopic interference morphology reconstruction method based on the mixing interference fringe is high in measurement precision, high in anti-interference capability and simple in system, and is suitable for three-dimensional morphology detection of the micro-nano structure.