MagicBook: Transitioning between Reality and Virtuality Mark Billinghurst Hirokazu Kato 1 Ivan Poupyrev 1 HIT Laboratory Faculty of Information Sciences Interaction Lab University of Washington Hiroshima City University Sony CSL Box 352-142, Seattle 3-4-1, Ozaka-higashi, Asaminami-ku 3-14-13 Higashi-Gotanda WA 98195, USA Hiroshima 731-3194, JAPAN Tokyo 141-0022, JAPAN grof@hitl.washington.edu kato@sys.im.hiroshima-cu.ac.jp poup@csl.sony.co.jp 1 Also affiliated with ATR MIC Labs, 2-2 Hikaridai, Seika-cho, Soraku-gun, Kyoto 619-0288, Japan ABSTRACT The MagicBook explores how interfaces can be developed that allow for seamless transition between Physical Reality, Augmented Reality (AR), and immersive Virtual Reality (VR) in a collaborative setting. The MagicBook is a normal book and can be read without any additional technology. However, when book pages are viewed through a handheld display three-dimensional virtual images appear overlaid on them. Readers can view these AR scenes from any perspective and can also fly into the scenes and experience them as an immersive VR world. VR users can see other VR users represented as life-sized virtual avatars, while AR users will see VR users as miniature avatars in the scene. Keywords Augmented Reality, Collaboration, CSCW. INTRODUCTION Many computer interfaces have been developed which explore collaboration in a purely physical setting, in an AR setting, or an immersive VR environment. Milgram’s taxonomy places these interfaces along a Reality-Virtuality continuum [1]. Moving from left to right the amount of virtual imagery increases and the connection with reality weakens. However, collaborative interfaces typically do not allow people to move easily along this continuum. Fig 1: Milgram’s Reality-Virtuality Continuum VR and AR are complimentary and the best type of collaborative interface depends on the nature of the task [2]. If collaborators want to experience a virtual scene from different scales then immersive VR may be ideal, but if they want to have a face-to-face discussion while viewing a virtual model an AR interface may be best. So an interesting question is how to support seamless transitions along the Reality-Virtuality continuum. THE MAGICBOOK The MagicBook project explores transitional interfaces and how a physical object can be used to seamlessly transport users along the Reality-Virtuality continuum. We use a real book, so people can turn the pages, look at the pictures, and read the text without any additional technology. If they look at the pages through an AR display they see three- dimensional virtual models appearing out of the pages (fig. 2). The models appear attached to the real page so users can see the scene from any perspective simply by moving themselves or the book. Finally, readers can fly into the virtual scene and experience the story immersively (fig. 3). Fig 2: AR Scene Fig 3: Immersive VR Scene The MagicBook supports collaboration on three levels: As a Physical Object: Similar to using a normal book, multiple users can read together. As an AR Object: Users with AR displays can see virtual objects appearing on the pages of the book. As an Immersive Virtual Space: Users can fly into the virtual space together and see each other represented as virtual avatars in the story space (figure 3).