TOUCHify: Bringing pen-based touch screen functionality to flat panel display screens

The past years have seen a rapid proliferation of flat panel display (FPD) screens that are available in almost all households and that have almost completely displaced cathode ray tube screens. While these screens have a great potential for serving as unobtrusive user interaction devices, usually only a small portion of FPDs are built to incorporate touch screen functionality due to the cost it entails. Several attempts have been made to economically transform existing FPDs into touch-enabled screens using either fingers, pens or styluses. In this paper we present TOUCHify, a novel approach that uses a dynamic pixel pattern seamlessly integrated into an application´s output on display, together with a digital microscopic pen. The pen is able to detect the embedded pixel pattern which, in turn, allows the application to react to user interaction. This enables pen-based touch screen functionality on arbitrary FPDs. An evaluation of the TOUCHify prototype with a healthcare feedback form emulator in an ambient assisted living scenario shows the effectiveness of the approach.