Subjective accommodation refractive error models are essential for implementing adaptive vision correction devices that utilize varifocal optics. This article describes compact empirical models of subjective accommodative refractive errors in subjects with advanced presbyopia. The models are based on measurements of subjective refractive errors from fifteen presbyopes over the age of 45 using commercially available focus-tunable eyeglasses under three different illumination conditions over a 3.08D accommodation stimulus range. The resulting average residual root-mean-squared (RMS) error values for the best fitting 8-parameter model was 0.25D compared to an average RMS error of 0.4D for the conventional DDF and HHG models. The RMS error for the best-fitting model is below the average refractive error of the human eye.
