title: Depth measurements through controlled aberrations of projected patterns.
abstract: Three-dimensional displays have become increasingly present in consumer markets. However, the ability to capture three-dimensional images in space confined environments and without major modifications to current cameras is uncommon. Our goal is to create a simple modification to a conventional camera that allows for three dimensional reconstruction. We require such an imaging system have imaging and illumination paths coincident. Furthermore, we require that any three-dimensional modification to a camera also permits full resolution 2D image capture.Here we present a method of extracting depth information with a single camera and aberrated projected pattern. A commercial digital camera is used in conjunction with a projector system with astigmatic focus to capture images of a scene. By using an astigmatic projected pattern we can create two different focus depths for horizontal and vertical features of a projected pattern, thereby encoding depth. By designing an aberrated projected pattern, we are able to exploit this differential focus in post-processing designed to exploit the projected pattern and optical system. We are able to correlate the distance of an object at a particular transverse position from the camera to ratios of particular wavelet coefficients.We present our information regarding construction, calibration, and images produced by this system. The nature of linking a projected pattern design and image processing algorithms will be discussed.
authors.affiliation: University of Arizona College of Optical Sciences, 1630 E. University Blvd., Tucson, AZ, USA. gcb@email.arizona.edu
authors.forename: Gabriel C
authors.initials: GC
authors.lastname: Birch
authors.forename: J Scott
authors.initials: JS
authors.lastname: Tyo
authors.forename: Jim
authors.initials: J
authors.lastname: Schwiegerling
mesh_terms: D000465:Algorithms; D016477:Artifacts; D007089:Image Enhancement / Q000295:instrumentation*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation*; D008029:Lighting / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity