Does the Accommodative Mechanism of the Eye Calibrate Itself Using Aberration Dynamics? – Oral Paper

Kotulak and Schor have suggested that the accommodative mechanism of the human eye can determine the required response from the changes in retinal image contrast associated with the microfluctuations of accommodation. As other aberrations also display dynamic behaviour, they may too have an input in this self-calibration mechanism. An adaptive optics system with separate measurement and manipulation channels was developed to investigate this possibility. A rotating diffuser is used to reduce laser speckle. The light hits the 37-element piezoelectric deformable mirror twice to increase its effective stroke. The accommodation response to 0.75 D step changes in target vergence whilst inverting selective aberrations during the latency period was studied in three subjects. In two subjects, inversion of astigmatism and spherical aberration showed the greatest effect; suggesting that for these subjects the eye potentially calibrates itself using information obtained from the aberration dynamics. One subject could not accommodate even with the aberrations left unchanged, and so may require chromatic aberration to guide the accommodative mechanism.