ABSTRACT
Schematic eyes can be developed at different levels of complexity. Simple models, involving as few as a single optical surface, simplify calculations but can only give limited approximations to the real eye’s optical performance. Complex models involving multiple aspheric surfaces, gradients of refractive index, surface tilts and misalignments, etc., can give a much more complete description of the eye’s normal levels of aberration and off-axis optical performance, but involve much more elaborate calculations.
