Measuring fixation disparity with infrared eye-trackers

Maria De Luca; Donatella Spinelli; Pierluigi Zoccolotti; Fabrizio Zeri

doi:10.1117/1.3077198

1 January 2009 Measuring fixation disparity with infrared eye-trackers

Maria De Luca, Donatella Spinelli, Pierluigi Zoccolotti, Fabrizio Zeri

Author Affiliations +

Journal of Biomedical Optics, Vol. 14, Issue 1, 014013 (January 2009). https://doi.org/10.1117/1.3077198

Abstract

Fixation disparity, that is, misalignment of the gaze direction of both eyes, may be observed in static conditions (through standard optometric evaluation) and dynamic conditions (through eye movement recording). A computation method is presented to determine vergence angles and fixation disparity from gaze positions as commonly recorded by infrared eye-trackers when a participant looks at a personal computer (PC) screen. Eye-tracking devices provide gaze position in coordinates relative to the bidimensional screen surface. From these data, vergence angles can be calculated by trigonometric triangulations; fixation disparity is then calculated from the vergence angles. The application of the procedure to the recordings of one participant is described. To control for the effective alignment of the two eyes on the target during binocular calibration, a procedure based on the dichoptic presentation of nonius lines was used. The recordings confirm that computation and the dichoptic calibration procedures ensure reliable measures of vergence and fixation disparity. The usefulness of this approach with infrared recording of eye position is discussed.

©(2009) Society of Photo-Optical Instrumentation Engineers (SPIE)

Citation Download Citation

Maria De Luca, Donatella Spinelli, Pierluigi Zoccolotti, and Fabrizio Zeri "Measuring fixation disparity with infrared eye-trackers," Journal of Biomedical Optics 14(1), 014013 (1 January 2009). https://doi.org/10.1117/1.3077198

Published: 1 January 2009

ACCESS THE FULL ARTICLE

JOURNAL ARTICLE
8 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY