On Object Selection in Gaze Controlled

The fascination of gaze control Controlling computers by gaze is a fascinating under-taking, for users as well as for researchers. The user’s fascination is two-fold; on the one hand, system control seems to be somehow magical, which might be due to it’s intangibility. On the other hand, one gets feedback about one’s own eye movements, which one is usually unaware of. For researchers, this fact is also of interest: Since the gaze moves towards objects and areas of interest, it pro-vides valuable information about the focus of attention and the users intentions. With intelligent algorithms, the cursor position can thus not only been adjusted on the basis of the current gaze position, but even be predicted. In such a way, gaze control can be used to pre-activate certain areas of interest, objects, or actions. This com-prises the term of “attentive input ” (Zhai, 2003). The vi-sion of attentive input is that, by gaining information about a user’s gazing behaviour, a system can react or, even better, predict his intentions and can thus provide suitable assistance. Another important feature of gaze control is its veloc-ity: An object can be looked at much faster than it can be reached by hand or any tool. This speed advantage might contribute also to the user’s fascination. Moreover, it is clearly one advantage over any other interaction tech-nique known hitherto. Despite these useful qualities, the implicit nature of gazing bears also several disadvantages. The most obvi-ous and probably also most disturbing one is the inad-equateness of implicit movements for performing explicit actions, and thus for achieving explicit goals. But of course, the most important tasks in computer control re-quire explicit control. In this paper we provide an overview of selection metaphors which have been developed and used in the past twenty years and describe the efforts, qualities and challenges of using gaze for explicit computer control. Task requirements: Selecting and confirming The majority of subtasks during computer control can be divided into two main classes; namely navigation tasks and object selection tasks. Examples for navigation ar