2. Background Screen Projector - One projector - - Two projectors - - Tiled projectors -

3. Screen Projector A user is allowed to hold up a projector and turn it freely. Aim of this study

4. Brightness of screen

5. Pm = f S ( – /2, D ) Pn = f S ( + /2, D ) f S (, D ) gives the brightness at C.

6. Brightness of screen Panning Panning + Tilting

7. Look of our system Framework of our system Camera Projector Screen Map Viewer

8. Map Viewer (our system + Google Earth) Map Viewer Panning the projector Right and Left A user is allowed to see the map by handling the projector. Stepping back

9. Technique to locate a projector by using difference in brightness on the screen. Map Viewer to see the map by handling the projector. Conclusions