Fig. 1. Schematic of generation of backscattered electrons (a), and simplified diagram of transmission X-ray tube model for simulation (b)

Fig. 2. Comparison between simulated data of new model and literature results

Fig. 3. Backscattered electron energy spectra (a) and position distribution (b) without internal collimator (color online)

Fig. 4. Backscattered electron energy spectra (a) and position distribution (b) with internal collimator (color online)

Fig. 5. FWHM sizes of transmission X-ray tube exit beams(color online)

Fig. 6. Change in photon yield of different target materials (a) and change in growth rate (b)

Fig. 7. Comparison of X-ray energy spectra of Ag targets under different tube voltages