Article

Least-squares calibration method for fringe projection profilometry considering camera lens distortion

School of Mechanical and Aerospace Engineering, Nanyang Technological University, Nanyang Avenue, 639798, Singapore.
Applied Optics (Impact Factor: 1.78). 03/2010; 49(9):1539-48. DOI: 10.1364/AO.49.001539
Source: PubMed

ABSTRACT

By using the least-squares fitting approach, the calibration procedure for fringe projection profilometry becomes more flexible and easier, since neither the measurement of system geometric parameters nor precise control of plane moving is required. With consideration of camera lens distortion, we propose a modified least-squares calibration method for fringe projection profilometry. In this method, camera lens distortion is involved in the mathematical description of the system for least-squares fitting to reduce its influence. Both simulation and experimental results are shown to verify the validity and ease of use of this modified calibration method.

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Available from: Lei HUANG, Jan 28, 2015
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    • "The spatial resolution of the captured images was 53 px per millimeter (mm). The optical axis of the camera was perpendicular to the reference plane, while the line connecting the projector and camera were parallel to the reference plane accordingly to Huang et al. (2010). The distance between the CCD and the projector d was 80 mm, the distance between CCD and the reference plane was 225 mm, and between the projector and the reference plane was 239 mm (Figure 1). "
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    ABSTRACT: 2015. A novel application of the white light/fringe projection duo: recovering high precision 3-D images from fossils for the digital preservation of morphology. Palaeontologia Electronica 18.2.6T: 1-13 palaeo-electronica.org/content/2015/1272-3d-fossil-images-and-white-light ABSTRACT There has been long historical interest in digital preservation of morphological features of biological materials, especially because often the preservation of sensitive molecules is critical for evolutionary studies. To this end, we successfully applied the recent advances of the fringe projection profilometry technique, in conjunction with white light and a new phase algorithm, to digitalize the shape of a fossil rodent hemi-mandible. We were able to generate a cloud of points in an array of data that allowed us to plot a three-dimensional (3-D) digital restoration of the entire fossil sample. The maximum resolution of this system is given by the diffraction limit (in the order of microns), and we show that this enhanced system can be used with objects in a range of 1-30 mm, minimizing the systematic errors induced by small vibrations or light fluctuations and, consequently, improving the signal-to-noise ratio of the recovered cloud data. This is a useful tool to preserve 3-D images of fossils and other biological objects for which rather detailed morphological information is required, like in research studies for biologists and paleontologists or, as in the present case, when researchers need a morphological replica because the sample will be destroyed for ancient DNA extraction.
    Full-text · Article · Aug 2015 · Palaeontologia Electronica
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    • "The calibration of the system242526 can be accomplished by using a number of precise gage blocks of different heights. Such a calibration method can yield high accuracy in 3D object measurements, but it is not very practical for broad applications due to the cost and challenges of manufacturing highly accurate and precise gage blocks with various sizes. "
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    Full-text · Article · Nov 2014 · Applied Optics
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    • "Existing calibration methods of phase-based 3D systems can be categorized into model-based [3] [4], polynomial [5] [6] and least-square [7] [8]. All the methods need an accurately translated plate or a 3D standard gauge block. "
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    ABSTRACT: One important step of phase-based 3D imaging system is calibration, which defines the relationship between phase and depth data. Existing calibration methods are complicated and hard to carry out because of using a translation stage or gauge block in a laboratory environment. This paper introduces an automatic calibration method by using a white and black checkerboard and a white plate having discrete markers with known separation and automatically determining each marker's position. The checkerboard determines the internal parameters of a CCD camera, while the plate gives depth and phase data to establish their relationship for each pixel. Experimental results and performance evaluation show that the proposed calibration method can reliably build up the accurate relationship between phase and depth data with an automatic way.
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