LETTER TO THE EDITOR: Point spread function of the human eye obtained by a dual double-pass method

We present an experimental method to obtain the point spread function (PSF) of human eyes, based on two techniques: the conventional symmetric double-pass method and the recently introduced asymmetric one-and-a-half-pass method. The symmetric double-pass method provides the autocorrelation of the retinal PSF and thus, the modulation transfer function (MTF). Here, we show that the double-pass MTF can be combined with partial phase information provided by the one-and-a-half-pass method to estimate the PSF. Two reconstruction methods were used, depending on the relative contribution of diffraction and aberrations. When aberrations are dominant (large pupils), the PSF can be obtained directly by combining the modulus and phase. When aberrations are small (small to medium pupils), however, a partial phase-retrieval algorithm has to be applied. In agreement with previous findings, the PSFs show substantial intersubject variability and for large pupils, they display the characteristic ray-pattern of star images.