Compact Models of Presbyopia Accommodative Errors for Wearable Adaptive-Optics Vision Correction Devices

Abstract

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 8parameter 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.

Refractive-type Varifocal Liquid-crystal Fresnel lenses for smart contacts

“…The Zernike coefficients of the VLCF system also indicated no significant change in aberration measurements before and after LC filling. The maximum difference in RMS wavefront aberrations before and after LC filling was measured to be 0.04 µm, which is significantly lower than the average RMS aberration of the human eye (0.3µm) [4], [7]. The offset lenses with appropriate optical power of 16.67 D were also similarly fabricated.…”

“…Alternate to the zoned approach, one can utilize adaptive optics-based solutions for presbyopia correction. Recently there has been a surge in efforts to develop and deploy smart autofocusing eyeglasses which comprise of adaptive tunable lenses that can automatically focus on the object of interest [3]- [7]. However, in its current form, due to their inherent requirement of very large aperture tunable lenses, autofocusing eyeglasses suffer from several problems.…”

Ultralow Power On-the-Eye Vergence and Distance Sensing Through Differential Magnetometry

“…The VFL provides the optical power (that roughly adds up to the individual's incorrect crystalline power) necessary to produce sharp images for a given object distance. This is specified by a characteristic curve fVFL(u) tailored for a specific individual [35]. The varifocal accommodation restoration technique thus requires the measurement of the distance between the object and the eye.…”

“…As illustrated in Figure 1, the clear vision slice is bounded by the DOF far FDOF and near NDOF limits. For the human eye, the DOF, NDOF and FDOF are functions of the eye pupil aperture diameter D and power of the crystalline lens [35]- [38]. (2…”