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Correlation between optical and psychophysical parameters as a function of defocus.

Eloy A Villegas·Concepción González·Bernard Bourdoncle·Thierry Bonnin·Pablo Artal
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Abstract

PURPOSE: To evaluate how ocular optical image quality and psychophysical estimates of visual performance compare to each other as a function of defocus. METHODS: We measured the optical modulation transfer function using a double-pass apparatus and psychophysical estimates of visual performance: contrast sensitivity function (CSF) and visual acuity. Both sets of data were obtained under the same optical conditions. RESULTS: We measured optical and psychophysical parameters as a function of defocus. We studied the correlation between optical parameters (Strehl ratio and the logarithm of the volume in the double-pass image [log_Vol D-P]) and psychophysical parameters (the area under the fitted CSF represented in a logarithmic scale with the spatial frequency in linear scale [Area CSF-log_lin] and visual acuity) for different values of defocus. CONCLUSIONS: Strehl ratio is well correlated with the psychophysical estimates of the visual performance for moderate amount of defocus (within 1 D), whereas the other parameter (log_Vol D-P) is well correlated for larger ranges of defocus (within 2 D) and for different pupil diameters. These results suggest that optical measurements could be used for clinical testing of ophthalmic optics.

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AdultContrast SensitivityFemaleHumansMalePsychophysicsRefraction, OcularRefractive ErrorsVisual AcuityJournal ArticleResearch Support, Non-U.S. Gov't

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Eloy A Villegas, Concepción González, Bernard Bourdoncle, Thierry Bonnin, Pablo Artal. 2002. Correlation between optical and psychophysical parameters as a function of defocus.. https://doi.org/10.1097/00006324-200201000-00014

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