Hotaru: Intuitive Manipulation Techniques for Projected Displays of Mobile Devices.

Mobile devices (cellular phone, PDA, etc.) have so far been personal tools. Due to their evolution to multi-functionality, however, the devices have begun to be used by multiple people in co-located situations. This paper discusses near future technologies: a mobile device with a projector and intuitive manipulation techniques by using a video camera mounted on the device. In today's technologies, it is difficult to realize a mobile device with a small and lightweight projector that still retains the feature of mobility. Therefore, we have developed a system to project displays of mobile devices on a table, a floor, or a wall, by tracking their three-dimensional positions and orientations and using an existing LCD projector. The proposed system called Hotaru (a firefly, in English) allows users to annotate/rotate a picture or a document in a mobile device by touching its projected display with their fingers. Users can intuitively transfer a file between multiple devices by making their projected displays overlapped. Informal evaluations of Hotaru indicated that the proposed manipulation techniques could effectively support multiple people in co-located situations in conducting their tasks. [ABSTRACT FROM AUTHOR]