Table 1 Optical system specifications for the miniature imager and the metaform.

ParameterSpecification
Object distance85 mm
Object size8.5 mm by 5 mm
Illumination wavelength632.8 nm
Effective focal length4 mm
F/#4.67
Magnification0.0453
Metasurface dimensions2 mm by 1.5 mm
Freeform substrate shapeX-toroid
Rx, Ry−8.24 mm, −7.78 mm
α, β, γ0.2434, −0.0015 mm−2,
−0.0017 mm−2