Fig. 1. Schematic of multi-system synergistic measurement

Fig. 2. Schematic of the normalization of measurement coordinate system

Fig. 3. Schematic of positioning curvature center

Fig. 4. Schematic for optical axis characterization

Fig. 5. Skematic diagram for characterization of optical axis positions

Fig. 6. Skematic diagram for optical axis attitude

Fig. 7. Coordinate system establishment and reference unification

Fig. 8. Flow chart for mechanical‒optic reference transferring

Fig. 9. Schematic of coordinate relationship under various coordinate systems

Fig. 10. Skematic for optical collimating path

Fig. 11. Skematic diagram for offset optical path

Fig. 12. Experimental setup for central alignment resolution

Fig. 13. Skematic diagram of selected measurement points

Fig. 14. Analysis of position error for optical axis calibration. (a) Histogram of position error; (b) integral curve for position error

Fig. 15. Skematic diagram of the optical axis eccentricity

Fig. 16. Analysis of eccentricity error for optical axis calibration. (a) Histogram for eccentricity error; (b) integral curve for eccentricity error

Fig. 17. Skematic diagram for assembly and alignment of off-axis three-mirror optical system

Fig. 18. Skematic diagram for optical inspection using 4D interferometer

Fig. 19. Inspection results of wave aberration at central field view. (a) RMS is 0.0552λ; (b) RMS is 0.0608λ; (c) RMS is 0.0535λ