Table 1. Fundus camera and fixation target design specifications.

Specification	Value
Full field of view	≥ 30° of visual angle
Eye relief	≥ 90 mm
Sphere prescription range	−20 to +10 D
Focusing method	Afocal (Badal) zoom relay
Spectral bandwidth	Fixation/stimulation: 455 - 625 nm Fundus imaging: 920 - 960 nm
Design performance	< λ/14 RMS wavefront for all field angles & wavelengths
As-built performance	< λ/10 RMS wavefront for all field angles & wavelengths
Spherical aberration correction	0.138 µm (Zernike spherical) over a 5.7 mm pupil [42]*
Longitudinal chromatic aberration	1.09 D (455-625 nm) [38], 0.02 D (920-960 nm) [39]

* Porter et al. [42] followed ‘OSA standard for reporting the optical aberrations of eyes’ [58], which uses Zernike polynomials normalized over the unit circle area. Code V (Synopsys Inc., Mountain View, CA, USA), uses a different normalization, which requires the following scaling: ${\left\{Z_4^0\right\}}_{\text{Norm}}=\sqrt{5}{\left\{Z_4^0\right\}}_{\text{Code V}}$.