Inverted FTIR: easy multitouch sensing for flatscreens

The increased attention which multitouch interfaces have received in recent years is partly due to the availability of cheap sensing hardware such as FTIR-based screens. However, this method has so far required a bulky projector-camera setup behind the screen. In this paper, we present a new approach to FTIR sensing by "inverting" the setup and placing the camera in front of the screen. This allows the use of unmodified flat screens as display, thereby dramatically shrinking the space required behind the screen and enabling the easy construction of new types of interactive surfaces.