A collaborative effort between researchers at the University of Siegen (Siegen, Germany), the University of Lübeck (Lübeck, Germany), Christian-Albrechts-University (Kiel, Germany), and the Technical University of Denmark (Copenhagen, Denmark) is advancing revolutionary time-of-flight (TOF) camera technology. Using techniques borrowed from light detection and ranging (LIDAR), TOF cameras incorporate range-imaging sensors—low cost, compact devices that use either a phase measurement or optical-shutter technology that can be realized with either CMOS or CCD designs for acquiring real-time 3-D distance information useful for gaming, virtual reality, and computer-graphics applications.

Currently, laser triangulation techniques and stereo vision fall short of providing full-range, high-resolution distance information in real time at low cost. Manufacturers of TOF cameras such as PMDTechnologies (Siegen, Germany), MESA Imaging (Zurich, Switzerland), and Canesta (Sunnyvale, CA) use an intensity-modulation principle based on on-chip correlation (mixing) of the reflected signal from a modulated near-IR source illuminating the scene and a reference signal, while companies such as 3DV Systems (Yokneam, Israel) use an alternative TOF method based on measuring time of flight using a fast shutter technique with several exposures. Although TOF cameras display relatively large measurement errors compared to high-precision laser scanners, their small size, low cost, and high frame rates make them suitable for a variety of interactive 3-D applications. Contact Andreas Kolb at andreas.kolb@uni-siegen.de.

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