2. Background - Touch Panel - The position you have touched is detected by the sensor embedded in the surface.

3. - Screen - If sensors cannot be embedded in the surface, what alternative way is available ? Background - Projector -

4. - Cam - - Cam 2 - - Cam 1 - Use two cameras Use one camera Touched!! Background Touching is not detected instantly Touching is detected instantly

5. - Cam - - Projector - - Screen - We use ONE camera to determine instantly if a fingertip has touched a screen. Aim of this study Touched!!

6. Fingertip shadow in touching a screen When a fingertip is not on the screen, When a fingertip is on the screen,

7. Fingertip is NOT on the screen - Screen - Fingertip is on the screen - Screen - Fingertip shadow in touching a screen

8. When do clickin, clickout, and move occur ? Fingertip shadow in touching a screen clickin clickout move

9. Fingertip shadow in touching a screen click, db-click, and drag are formed by clickin, clickout, and move. click clickin+clickout click db-click clickin+clickout +clickin+clickout db-click drag drag clickin+move

10. Look of our system Framework of our system Camera Projector Screen Application

11. Map View Application Zooming in, scrolling, and zooming out a map A user is allowed to manipulate a map by touching.

12. Application Writing “Hello!” MS Paint

13. Fingertip-shadow for click, db-click, and drag on a wall We focused on fingertip shadow in order to determine if the fingertip has touched a screen. We built a system providing click, db-click, and drag. We applied the system to two applications. Conclusions