LaserPen: a new pointing device for a beam projector

We propose a new pointing device for a beam projector that we call a LaserPen system. The basic idea is to detect a laser spot on the screen and use its coordinates to control the GUI cursor so that the two may coincide. While this idea can be easily realized by using a camera and a simple image processing technique, the novel part of our implementation is to share the same optical channel among a projector and a camera so that the focusing and alignment of a camera may be done at the same time as a projector is focused and aligned. In a usability test in comparison with other pointing devices, we could confirm that, due to its directness, the LaserPen system have the potential to become a highly favorable pointing device for a beam projector.