@CONFERENCE\{IMM2010-05976,
    author       = "O. V. Olesen and M. R. J{\o}rgensen and R. R. Paulsen and L. H{\o}jgaard and B. Roed and R. Larsen",
    title        = "Structured Light {3D} Tracking System for Measuring Motions in {PET} Brain Imaging",
    year         = "2010",
    pages        = "76250X-1-11",
    booktitle    = "Proceedings of the {SPIE} - Medical Imaging 2010: Visualization, Image-Guided Procedures, and Modeling",
    volume       = "7625",
    series       = "",
    editor       = "",
    publisher    = "",
    organization = "",
    address      = "",
    url          = "http://www2.compute.dtu.dk/pubdb/pubs/5976-full.html",
    abstract     = "Patient motion during scanning deteriorates image quality, especially for high resolution {PET} scanners. A new proposal for a {3D} head tracking system for motion correction in high resolution {PET} brain imaging is set up and demonstrated. A prototype tracking system based on structured light with a {DLP} projector and a {CCD} camera is set up on a model of the High Resolution Research Tomograph (HRRT). Methods to reconstruct {3D} point clouds of simple surfaces based on phase-shifting interferometry (PSI) are demonstrated. The projector and camera are calibrated using a simple stereo vision procedure where the projector is treated as a camera. Additionally, the surface reconstructions are corrected for the non-linear projector output prior to image capture. The results are convincing and a first step toward a fully automated tracking system for measuring head motions in {PET} imaging."
}