% Lens 4 (Element 5):
R1        R1_5        Radius of curvature, surface 1
R2        R2_5        Radius of curvature, surface 2
Tc        Tc_5        Center thickness
d0        d0_5        Outer diameter
d1        d1_5        Diameter, surface 1
d2        d2_5        Diameter, surface 2
d1_clear  d1_clear_5  Clear aperture diameter, surface 1
d2_clear  d2_clear_5  Clear aperture diameter, surface 2
nix       0           Local optical axis, x-component
niy       0           Local optical axis, y-component
niz       1           Local optical axis, z-component