Laser Pointer Tracker System was an old project proposed and executed by John Hu 4 years ago.
It was a software-based human computer interaction device. It could detect the laser pointers by computer built-in camera. It used computer vision to locate the position of laser pointers in camera and coverted them to computer coordinate system.
The first example was to control a power point presentation with a laser pointer and gestures. This example is made with Win32 API and our owned gesture detections.
The second example was made by Flex. It is an interactive system, multile-touches photo gallery, and google map: