Absolute calibration for Fizeau interferometer with the global optimized shift-rotation method

•We present a global optimized shift-rotation method.•A method to decrease the errors of rotations and translations is presented.•Error analysis of shift-rotation is presented.•Experimental results with detailed comparisons are given.

We present an absolute calibration method for Fizeau interferometer with global optimized shift-rotation, which requires rotational and translational measurements. With a data matching method to decrease the alignment error of rotations and translations, the accuracy can be guaranteed. The global optimized shift-rotation method can obtain the surface deviation accurately of both the reference and test surfaces in terms of Zernike polynomials. Experiments have been implemented to verify the validity of the absolute calibration, and the results show that the reference surface deviation agrees well with the calibration result of conventional two-sphere method. Simulations were performed to evaluate the errors introduced by rotations and translations.