Exact multi-shear reconstruction method with different tilts in spatial domain

An improved zonal algorithm based on the multi-shear interferometry with different tilts is proposed to reconstruct two-dimensional wavefront exactly. The method allows large shear and high lateral resolution be achieved simultaneously. Due to environment vibration and mechanical misalignment, different tilt errors added in the measured wavefront will result in unknown and mismatch bias in the difference wavefronts. The effect of tilt errors in multi-shear method is analyzed and an improved zonal method is proposed to deal with tilt errors, which is easy to implement. Numerical simulations are executed and the results indicate that the improved algorithm is immune to tilt errors and has good noise suppression capabilities. In the experiment, we combine multi-shear method but using a Fizeau interferometer. The result demonstrates the effectiveness of the proposed algorithm.