A semi-automatic realtime calibration technique for a handheld projector

In this paper, a semi-automatic realtime calibration technique for a handheld projector is described. The proposed technique always keeps a shape of a projected screen rectangular on a specified projection surface, while a user continuously changes his standing position or the pose of the projector. The technique is especially useful for a future mobile phone with a built-in projector that allows a user to project its screen onto any surface in any location and share the screen with multiple people. Informal evaluations using the technique have been conducted to identify the level of its acceptability by users and to find problems to be improved. An example entertainment application to explore possibilities of the proposed technique has been developed.