Design of optical system for binocular fundus camera

Figures & data

Figure 1. Optical system for binocular fundus camera.

Figure 2. Gullstrand Le Grand eye model.

Figure 3. Two forms of stereomicroscope (a) Parallel optical system and (b) Tilted optical system.

Figure 4. Diagram of imaging system.

Figure 5. Diagram of illumination system.

Figure 6. Curves of Modulation Transfer Function (MTF).

Figure 7. Field curvature and distortion curves.

Figure 8. Chromatic aberration curves.

Table 1. Relational expressions of lens parameters with the change of human eye diopters.

Lens Parameters	Relationship between lens parameter and diopters A
Anterior lens radius R3	R3(A)=10.2-1.75⋅ln(A+1)
Posterior lens radius R4	R4(A)=-6+0.2294⋅ln(A+1)
Aqueous thickness D2	D2(A)=3.05-0.05⋅ln(A+1)
Lens thickness D3	D3(A)=4+0.1⋅ln(A+1)
Lens refractive index n3	n3(A)=1.42+9×10^-5⋅(10⋅A+A^2)

Figure 9. MTF curves with different diopters.

Figure 10. Simulation of illumination uniformity in fundus (a) Illumination annulus at the pupil of the eye and (b) Illumination spot at fundus.