Aspherical Surface Wavefront Testing Based on Multi-directional Orthogonal Lateral Shearing Interferometry

To overcome the phase sampling point limitations of testing aspherical surface wavefronts by using the traditional interferometers, we describe a high spatial resolution method of aspherical surface wavefront testing based on multi-directional orthogonal lateral shearing interferometry. In our investigation, we detailed description the methodology of multi-directional orthogonal lateral shearing interferometry, which includes theoretical foundations and experimental setup, presented simulations and experiments results. By establishing a relational model corresponding to multi-directional differential wavefront and differential Zernike polynomials, we presented the wavefront reconstruction of high spatial resolution based on multi-directional orthogonal lateral shearing interferometry. Theoretical calculation and simulation research on aspherical surface wavefront testing, we carried out the actual experimental measurement verification of aspherical surface wavefront with a certain asphericity. By comparing measurement with the measurement results of the LuphoScan profilometer, the relative measurement error precision of RMS was better than λ/100.