Experimental Comparison Of Measuring Performance Between The Eye Trackers Eyelink And Tobii

Measurement of eye movements is an important way to study cognitive processing. However, few researchers has explored the measuring performance of different kinds of eye trackers.We suppose: the temporal and spatial attributes of eye movements are objective to stimuli; data of eye movements should be able to represent these attributes and should be consistent if recorded by different eye trackers.Two eye trackers (Eyelink II and Tobii T120) were brought into comparison on the same experimental condition. And simple geometrical figures were chosen as stimuli. The results were as follows.1. There was significant difference in fixation counts and gaze time between the two eye trackers on the same experimental condition: fixation counts of Eyelink II were larger than that of Tobii T120; gaze time of Eyelink II was shorter than that of Tobii T120.2. Results received from the two eye trackers were significantly different on the design of line-dot stimuli pattern.3. Results received from the two eye trackers were the same on the design of visual angle: with the enlargement of visual angle, fixation counts increased and gaze time decreased.4. Results received from the two eye trackers were basically the same on the design of figure: line and T shape corresponded to least fixation count and longest gaze time; equilateral L shape and square corresponded to most fixation count and shortest gaze time.5. Results received from the two eye trackers were significantly different on the design of rotation angle.6. Results of gender received from the two eye trackers were different; results of different field cognition modes from the two eye trackers were different.7. The gaze-scan heat map recorded by the two eye trackers were basically the same. Fixations distributed mainly over the area of intersection and upper parts of the figures.