We present a new technique for managing visual clutter caused by overlapping labels in complex information displays. This technique, "label layering", utilizes stereoscopic disparity as a means to segregate labels in depth for increased legibility and clarity. By distributing overlapping labels in depth, we have found that selection time during a visual search task in situations with high levels of overlap is reduced by four seconds or 24%. Our data show that the depth order of the labels must be correlated with the distance order of their corresponding objects. Since a random distribution of stereoscopic disparity in contrast impairs performance, the benefit is not solely due to the disparity-based image segregation. An algorithm using our label layering technique accordingly could be an alternative to traditional label placement algorithms that avoid label overlap at the cost of distracting motion, symbology dimming or label size reduction.
Stephen Peterson, Magnus Axholt, Stephen R. Ellis