Measured double-pass intensity point-spread function after adaptive optics correction of ocular aberrations

Area of Science:

• Ophthalmology
• Optical Engineering
• Vision Science

Background:

• Ocular aberrations significantly impact visual acuity.
• Adaptive optics (AO) systems offer a method to correct these aberrations.
• Understanding the point-spread function (PSF) is crucial for assessing retinal image quality.

Purpose of the Study:

• To quantify the effect of adaptive optics correction on the ocular point-spread function (PSF).
• To compare the PSF at the fovea with and without AO correction.
• To evaluate the PSF at the fovea versus 2 degrees of eccentricity with AO correction.

Main Methods:

• Double-pass intensity point-spread function (PSF) measurements were performed in four subjects.
• A monochromatic light source (543 nm) and a 6.7-mm pupil were used.
• Measurements were taken at the fovea (with and without AO) and at 2 degrees eccentricity (with AO).

Main Results:

• AO correction narrowed the half-width at half-maximum (HWHM) of the PSF.
• The HWHM of the PSF was larger at 2 degrees eccentricity compared to the fovea with AO.
• Minimum HWHM values were 1.1 arcmin (dark pigmented eyes) and 1.6 arcmin (light pigmented eyes), 6-9 times diffraction-limited width.

Conclusions:

• Adaptive optics significantly improves retinal image quality by reducing ocular aberrations.
• The foveal PSF is superior to the paracentral PSF even with AO correction.
• The optical quality of the human eye remains limited by factors beyond diffraction and aberrations.