ROBUSTNESS OF VISUAL IMAGE QUALITY MEASURES AGAINST VARIOUS MONOCHROMATIC ABERRATIONS

We examine the correlation between subjective performance and objective image quality metrics, and show that an appropriately defined partial integral of the instrumental modulation transfer function (MTF), called MTFa, gives the best correlation with available psychophysical data, including those obtained by other investigators. The Strehl ratio and the radius that encircles 84% of the point-spread-function energy also show some correlation with subjective performance, but have considerable limitations. These results begin to make real the possibility that the image quality of visual instruments may be characterized by a single figure of merit within the isoplanatic patch, for all types of monochromatic aberrations.