Measurement of optical mirror with a small-aperture interferometer

Abstract

In this paper, the principle of subaperture stitching interferometry was introduced. A testing stage with five degrees of freedom for stitching interferometry was built. A model based on least-squares method and error averaging method for data processing was established, which could reduce error accumulation and improve the precision. A 100 mm plane mirror was measured with a 50 mm aperture interferometer by means of stitching interferometry. Compared with the results by a 100 mm interferometer, peak to valley (PV) and root mean square (RMS) of the phase distribution residual are \mathrm{0.0038}\lambda and \mathrm{0.0004}\lambda, respectively. It proved that the model and method are helpful for large optical measurement.

Keywords

subaperture stitching / interferometry / residual error

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant No. 61128012) and the Research Grants Council of the Hong Kong Special Administrative Region (No. 9041577).

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg