Computing high order wave aberration coefficients from variations of best focus for small artificial pupils

Van den Brink (1962) measured the variation of best focus of vertical bar targets through a 1.4 mm aperture across the pupil of the eye. He expressed his results in contour maps of isodioptric lines across the pupil. The relative focus of a portion of the pupil is a function of the curvature of the wave front within the aperture. The curvature, in turn, is proportional to the second derivative of the wave aberration polynomial. Thus it is possible to make estimates of some of the coefficients of the wave aberration polynomial from Van den Brink's focusing data. This has been done for two states of accommodation. The results indicate that the wave aberration polynomial of the measured eye contains some significant terms of a power higher than hitherto measured.