Fig. 1. The sketch of testing large mirror by pentaprism scanning

Fig. 2. Flow chart of testing large mirror by pentaprism scanning

Fig. 3. Flow chart of testing large mirror by SSI

Fig. 4. Sketch of testing large mirror by SSI

Fig. 5. Calculation in the overlapping areas

Fig. 6. Flow chart of testing low-order error of TMT-M3

Fig. 7. Sketch of setup of testing TMT-M3 by scanning pentaprism

Fig. 8. Sketch of testing TMT-M3 by Fizeau interferometry with 1.5 m reference mirror

Fig. 9. Distribution of subaperture of testing TMT-M3 by SSI

Fig. 10. Setup of testing the prototype by scanning pentaprism

Fig. 11. Testing results of the prototype by scanning pentaprism

Fig. 12. Setup and subaperture distrbution of testing the prototype by SSI

Fig. 13. Testing results of the prototype by SSI