Correlation between image quality and visual performance

In recent years, the use of devices that objectively measure visual quality has increased. The importance of these devices derives from the fact that objective data are correlated with visual performance, this being an essential question for the observer. In the present work, we used an aberrometer as well as a double-pass device to compile data, which we relate to information obtained from visual-performance tests (contrast-sensitivity function and discrimination capacity) under low-illumination conditions. We took data for 28 normal emmetropic observers and 30 patients operated upon for cataract surgery. The experimental data showed a significant correlation (higher for cataract patients) between objective and psychophysical measurements, revealing that these devices are useful for characterizing normal vision and for clinical applications.