A new method for calculating eye movement displacement from AC coupled electro-oculographic signals in head mounted eye–gaze input interfaces

Various eye movement measurement devices used in eye–gaze input interfaces are generally expensive or necessarily restrict the user's head motion. We proposed a novel eye–gaze input interface that combined a head mounted display with an electro-oculograph amplified via an AC coupling. Experiments were carried out to create a necessary calculation method for the displacement of an eye movement from an electro-oculograph amplified via an AC coupling. Offline and online analyses were performed to compare the new method of using integration to the previous method of using the maximum amplitude during an interval from 0 to 0 of the derivative AC-EOG. The mean accuracies of the choices increased from 88.8% to 96.7% in the case of 8 possible choices and from 72.8% to 86.4% in the case of 12 possible choices by using the integration instead of the maximum amplitude by the offline analyses. Moreover, the online analyses were done for confirmation of the calculation method of the displacement that was used with only the maximum displacement. For the designs with 8 and 12 possible choices, the mean accuracies of the choices were 95.3% and 88.5%, respectively.