Fig. 1. Principle of pentaprism scanning method

Fig. 2. Principle of nonuniform sampling pentaprism array. (a) Three-dimensional diagram of principle of nonuniform sampling pentaprism array; (b) principle of slope measurement in X direction; (c) principle of slope measurement in Y direction

Fig. 3. Reconstruction of wavefront with pentaprism array. (a) Simulated collimated wavefront; (b) random error in simulated collimated wavefront; (c) reconstructed collimated wavefront; (d) errors of reconstructed collimated wavefront; (e) simulated and reconstructed Zernike polynomial coefficients

Fig. 4. Robustness of reconstructing collimated wavefront. (a) PV values of errors; (b) RMS values of errors

Fig. 5. Scanning mechanism with pentaprism array

Fig. 6. Spot centroid displacement measured with pentaprism array scanning. (a) Spot centroid displacement in X direction; (b) spot centroid displacement in Y direction

Fig. 7. Roll angle of rail

Fig. 8. Spot centroid displacement with mechanical error eliminated

Fig. 9. Comparison between pentaprism array scanning measurement results and interferometric measurement results. (a) Pentaprism array scanning measurement results; (b) optical path of interferometric test; (c) interferometric measurement results; (d) Zernike polynomial coefficients of measurement results