Study On Phase - Shift Algorithm Of White Light Interferometric Microscope And Microstructure

With the development of precision machining technology, new requirements for ultra-precision detection technology are put forward. Micro three-dimensional morphology of precision optical components directly related to the performance of components. There are several methods to measure the microscopic three-dimensional morphology. High precision, high speed, and so does not damage the surface of the element is the advantages of using interference microscopy method for measuring cell surface which will replace the traditional contact methods gradually.The paper developed a set of white light interference microscopy system based on phase shifting interferometry and white light interferometry.Suitable for three-dimensional profile measurement of optics stairs, CGH, etc. White light LED as the light source, a closed-loop mode PZT as the phase shift mechanism. Improve the measurement accuracy and measurement efficiency. Developed image acquisition program based on the C# language.Studied the Carre white phase shifting interferometry algorithm. Realize the function of extracting microscopic three-dimensional contour information from a series of white light Interference figure. For the measurement results appear tilt, noise and other phenomena, we made a deal with the tilt and noise. We measured optics stairs.CGH using the white light interference microscopy system. The height of optics stairs is 108.63nm consistent with the nominal data. Measurement results for CGH is 69.58nm.With the increase of the scan spacing the accuracy of Carre white phase shifting interferometry algorithm declining.The scan spacing of 40-60nm is most suited to the experimental measurement. Relative repeatability error is 1.27%.