Much work has been done on the development of laser pointers as interaction devices. Typically a camera captures images of a display surface and extracts a laser pointer dot location. This location is processed and used as a cursor position. While the current literature well explains such a system, we feel that some important practical concerns have gone unaddressed. We discuss the design of such a tracking system, focusing on key practical implementation details. In particular we present a robust and efficient dot detection algorithm that allows us to use our system under a variety lighting conditions, and allows us to reduce the amount of image parsing required to find a laser position by an order of magnitude. Categories and Subject Descriptors: H.5.2 [Information Interfaces and Presentation]: User Interfaces, Input devices and strategies; I.3.1 [Hardware Architecture]: Input Devices; I.4.1 [Digitization and Image Capture]: Camera Calibration, Imaging Geometry General Terms: Algor...
Benjamin A. Ahlborn, David Thompson, Oliver Kreylo