Imperceptible depth shifts for touch interaction with stereoscopic objects

While touch technology has proven its usability for 2D interaction and has already become a standard input modality for many devices, the challenges to exploit its applicability with stereoscopically rendered content have barely been studied. In this paper we exploit the properties of the visual perception to allow users to touch stereoscopically displayed objects when the input is constrained to a 2D surface. Therefore, we have extended and generalized recent evaluations on the user's ability to discriminate small induced object shifts while reaching out to touch a virtual object, and we propose a practical interaction technique, the attracting shift technique, suitable for numerous application scenarios where shallow depth interaction is sufficient. In addition, our results indicate that slight object shifts during touch interaction make the virtual scene appear perceptually more stable compared to a static scene. As a consequence, applications have to manipulate the virtual objects to make them appear static for the user.