System settings
For the gaze angle experiments, comparisonbetween VG and Otowere performed in Shanghai Changzheng Hospital, while the tests between VG and ESC were performed at Fudan University affiliated Eye and ENT hospital. In either experiment, we were inclined to record from right eyes. Recording from the left eye only if the patient could not see the target from the right eye. All the experiments were applied by the trained examiners.