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PubMed · 7639307

Visual acuity modeling using optical raytracing of schematic eyes.

J E Greivenkamp·J Schwiegerling·J M Miller·M D Mellinger
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Abstract

PURPOSE: We developed a methodology to predict changes in visual performance that result from changes in the optical properties of the eye. METHODS: Exact raytracing of schematic eyes was used to calculate the point spread function and the modulation transfer function of the visual system. The Stiles-Crawford effect, photopic response, diffraction, and the retinal contrast sensitivity are included in the model. Visual acuity was predicted by examining the modulation of the resultant retinal image of a bar target and by determining when the modulation falls below a threshold value. Visual acuity was predicted for refractive errors ranging from 0 to 5 diopters and for pupil diameters ranging from 0.5 to 8 mm. RESULTS: Visual acuity predictions were compared to clinically found Snellen visual acuities and were found to be highly correlated (r2 = .909). CONCLUSIONS: This modeling technique shows promise as a means of evaluating clinical and surgical procedures before undertaking clinical trails.

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Contrast SensitivityHumansLightModels, BiologicalPupilRefractive ErrorsRetinaScattering, RadiationVisual AcuityJournal Article

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BibTeXRIS

J E Greivenkamp, J Schwiegerling, J M Miller, M D Mellinger. 1995. Visual acuity modeling using optical raytracing of schematic eyes.. https://doi.org/10.1016/s0002-9394(14)72611-x

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