Fig. 1. Schematic diagrams of the structure of standing wave accelerating tube. (a) Sectional structure diagram of standing wave accelerating tube; (b) amplification diagram of X-ray target structure and focal spot position

Fig. 2. Schematic diagram of "Sandwich" test method. (a) Structure of "Sandwich" test module; (b) test method

Fig. 3. Focal spot measurement results of "Sandwich" test method. (a) Film exposure image; (b) stripe enlarged image; (c) stripe gray distribution curve

Fig. 4. Comparison of the results of two measurements of the focal spot size by "Sandwich" test method. (a) Film exposure image; (b) stripe enlarged image; (c) comparison image of two measurement stripe gray curve

Fig. 5. Simulation results of "Sandwich" test method with different copper metal and plastic sheets combinations. (a) Combination 1; (b) combination 2; (c) combination 3; (d) combination 4; (e) combination 5; (f) combination 6

Fig. 6. Device structure schematic diagram of the slit translation scanning test method

Fig. 7. Working principle diagram of the slit translation scanning test method

Fig. 8. Experimental layout of the slit translation scanning test method

Fig. 9. Focal spot intensity distribution measured by the slit translation scanning test method

Fig. 10. Spatial resolution test chart of the high energy industrial CT. (a) CT scan image of wire pair; (b) gray curve of wire pair; (c) fitting MTF curve