Study On Compensation Technology Of Aspherical Surface Shape Measuring

With the successful application of aspheric elements in the optical design, optoelectronic devices for the first time achieve the simplification and miniaturization without changing the original optical properties. Because of the strict requirement for aspheric surface of the optical design, not only the test of aspheric optics is crucial, but also the development of optoelectronic devices. Depending on the design requirements, the aspheric element’s surface, size, and so on are different each other, the corresponding detection methods are very different. This paper discusses a new detection method, which does not use the traditional complex compensation lens group, directly use standard reference mirror and test mirror by interferometric method to test the smaller asphericity of aspheric surface.This paper studies the basic theory of aspheric optics and analyzies all kinds of aspheric optics surface testing method. On the basis of the existing theory and method, it discusses one kind of the surface measuring method which based on the double beam interference, by moving the test mirror, realize the mirror to be measured in different position detection for finding the interference phase picture and the phase points are converted to aspheric surface shape curve. The main work were researched the related theory of the interferometric neasurements of this method, and made the theoretical analysis and calculation. Feasibility is verified by Matlab software simulation analysis. It collects the interference pattern in experiment, then by matlab to filter, thinn and other treatmentthe for the interference pattern, finally fitted out the test aspherical surface shape. According to the requirements of the experiment, which is the method of detection of different positions, the paper designes a magnetic drive device, which is so-called phase compensation mobile device. When the test mirror was moved by the small amount, it achieves a change in the measurement position.Finally, with the building a detection device platform, it tests a parabolic mirror of 20 mm in diameter, and made date processing and error analysis. And the simulations show that the curved surface coordinate measuring based on the double beam interferometer can achieve detection of aspherical, but it has large errors under the current conditions.