On top of tabletop: A virtual touch panel display

In the real world, a physical tabletop provides public and private needs for people around the table. For competing scenarios such as playing a poker game or running a price negotiation around a tabletop system, privacy protection is obviously an indispensable requirement. In this work we developed a privacy-enhanced tabletop system composed of two kinds of displays, the tabletop surface and the virtual panel. All users share the large tabletop surface as a public display while every user is provided with a virtual panel emerging above the tabletop as a personal display for viewing private information. The virtual panel is an intangible, privacy-protected virtual screen created by a special optical mechanism which offers several promising characteristics, making it perfect to be integrated into a tabletop system. The contributions of the paper include: Firstly, we introduce a novel display technique, the virtual panel, into a tabletop system to build a privacy-enhanced tabletop system. Secondly, an analysis on display optics of the virtual panel is presented to explore other potentials of the display and to claim the feasibility of the proposed combination. Thirdly a computer vision-based interaction technique is proposed to provide direct-touch interaction for the virtual panel. Finally, we discuss a wide range of considerations on designing the user interface and interaction for the virtual panel.