Fig. 1. Optical system structure of the fundus camera

Fig. 2. Color image of the retina

Fig. 3. Eye model

Fig. 4. Structure of the ophthalmic lens. (a) Prototype; (b) optimization result

Fig. 5. Initial structure of the imaging system. (a) Without spectroscope; (b) with spectroscope

Fig. 6. Structure of the imaging system combined with eye model

Fig. 7. MTF curves of the imaging system

Fig. 8. Aberration analysis diagram. (a) Ray fan plot; (b) spot diagram; (c) field curvature and distortion

Fig. 9. Imaging simulation of the system. (a) Source image; (b) simulated image plane

Fig. 10. Schematic of the annular illumination

Fig. 11. Lighting system construction

Fig. 12. Schematic of the ring light source

Fig. 13. (a) MTF, (b) spot diagram and (c) relative illumination distribution of the illumination system