The following is a summary of “High-resolution eye-tracking via digital imaging of Purkinje reflections,” published in the May 2023 issue of Ophthalmology by Wu, et al.
Accurately measuring eye movements and determining the precise gaze location of an observer are fundamental requirements in the field of vision science. The dual Purkinje image (DPI) method has long been employed as a classical approach to achieve high-resolution oculomotor measurements. The method relies on analyzing the relative motion of reflections produced by two distinct surfaces in the eye: the cornea and the back of the lens. However, traditional implementation of the DPI method has been limited to fragile and complex analog devices, which are typically exclusive to specialized oculomotor laboratories.
For a study, researchers presented advancements in the development of a digital DPI system that overcomes the limitations of previous analog devices. Leveraging recent advancements in digital imaging technology, our system enables fast and highly precise eye-tracking without the complications associated with analog devices. The digital DPI system combines an optical setup devoid of moving components with a digital imaging module and dedicated software running on a high-speed processing unit.
Through experimentation involving both artificial eyes and human subjects, we demonstrate that the digital DPI system achieves subarcminute resolution at a sampling rate of 1 kHz. Furthermore, when combined with previously developed gaze-contingent calibration methods, the system allowed for accurate localization of the line of sight within a few arcminutes.
The development of this digital DPI system represented a significant advancement in oculomotor research, enabling researchers to obtain precise and real-time eye movement data in a more efficient and accessible manner. The system’s high resolution and integration with gaze-contingent calibration methods hold great potential for advancing our understanding of visual perception and eye movement dynamics in various scientific domains.
Source: jov.arvojournals.org/article.aspx?articleid=2785593
