Fig. 1. Pixel structure of the scintillation screen^［40］

Fig. 2. Influence of pixel hole size on performance of scintillation screen. (a) Relationship between size of pixel hole and the light emission of scintillation screen^[46]; (b) MTF curves of different pixel hole sizes^[45]

Fig. 3. Influence of GOS∶Tb scintillation screen thickness on performance of scintillation screen. (a) Relationship between thickness of GOS∶Tb scintillation screen and light emission; (b) MTF curve of different GOS∶Tb scintillation screen thicknesses^[42]

Fig. 4. Working principle of CCD image sensor^［52］

Fig. 5. Basic structure of CMOS image sensor^［52］

Fig. 6. Comparison of front illuminated and back illuminated CMOS image sensor structures^［59］

Fig. 7. Structure and principle of CMOS image sensor^［62］

Fig. 8. Structure of FOT coupling mode^［16］

Fig. 9. Structure of FOP coupling mode^［72］

Fig. 10. Structure of coupling mode of optical lens^[22]

Fig. 11. Structure of direct coupling mode^[40]