General defocusing particle tracking: fundamentals and uncertainty assessment

  title={General defocusing particle tracking: fundamentals and uncertainty assessment},
  author={Rune Barnkob and Massimiliano Rossi},
  journal={Experiments in Fluids},
Abstract General defocusing particle tracking (GDPT) is a single-camera, three-dimensional particle tracking method that determines the particle depth positions from the defocusing patterns of the corresponding particle images. GDPT relies on a reference set of experimental particle images which is used to predict the depth position of measured particle images of similar shape. While several implementations of the method are possible, its accuracy is ultimately limited by some intrinsic… 
Defocus particle tracking: a comparison of methods based on model functions, cross-correlation, and neural networks
Defocus particle tracking (DPT) has gained increasing importance for its use to determine particle trajectories in all three dimensions with a single-camera system, as typical for a standard
A fast and robust algorithm for general defocusing particle tracking
A fast and robust algorithm for performing GDPT, which is suitable for automatized and real-time applications, and is versatile and can be applied to different types of images (darkfield and brightfield).
DefocusTracker: A Modular Toolbox for Defocusing-based, Single-Camera, 3D Particle Tracking
DefocusTracker is an open-source toolbox based on the universal principles of General Defocusing Particle Tracking relying solely on a reference look-up table and image recognition to connect a particle’s image and its respective out-ofplane depth coordinate.
Development of multi-cycle rainbow particle tracking velocimetry improved by particle defocusing technique and an example of its application on twisted Savonius turbine
Rainbow particle tracking velocimetry (PTV) is a PTV method that enables three-dimensional (3D) three-component flow measurement using a single camera. Despite the advantage of its simple setup, the
Toward automated and real-time 3D PTV measurements for microfluidics
This work presents an algorithm for performing General Defocusing Particle Tracking in a fast, versatile, and automated manner and shows that the algorithm is versatile and can be applied to different types of images and that it is not sensitive to background or illumination fluctuations.
2D vs 3D tracking in bacterial motility analysis
This paper examines the errors introduced by tracking bacterial motion as 2D projections vs. 3D volumes under different circumstances: bacteria free in liquid media and bacteria near a glass surface and finds that while XYZ speeds are generally equal to or larger than XY speeds, they are still within empirical uncertainties.
Widely accessible method for 3D microflow mapping at high spatial and temporal resolutions
Advances in microfluidic technologies rely on engineered 3D flow patterns to manipulate samples at the microscale. However, current methods for mapping flows only provide limited 3D and temporal
Particle-size-dependent acoustophoretic motion and depletion of micro- and nano-particles at long timescales.
Three-dimensional measurements of particle-size-dependent acoustophoretic motion of microparticles with diameters from 4.8 μm down to 0.5 μm and particle trajectories in inhomogeneous fluids show focusing in the bulk of the microchannel at early times, even for the particles below the critical size, which clearly demonstrates the potential to manipulate submicrometer particles.
Three-dimensional close-to-substrate trajectories of magnetic microparticles in dynamically changing magnetic field landscapes
The transport of magnetic nano- or microparticles in microfluidic devices using artificially designed magnetic field landscapes (MFL) is promising for the implementation of key functionalities in
Effect of geometry on dielectrophoretic trap stiffness in microparticle trapping.
A 3-D microfluidic DEP device with an orthogonal electrode configuration that uses negative dielectrophoresis to trap spherical polystyrene micro-particles and the analysis of three different trap shapes provides important insights to predict trapping location, strength of the trapping zone, and optimized geometry for high throughput particle trapping.


General defocusing particle tracking.
A General Defocusing Particle Tracking (GDPT) method is proposed for tracking the three-dimensional motion of particles in Lab-on-a-chip systems based on a set of calibration images and the
Optimization of astigmatic particle tracking velocimeters
This paper focuses on the uncertainty of APTV in the depth direction, and derives the derivation of general criteria to minimize the overall error in APTV measurements and provide the basis for reliable uncertainty estimation for a wide range of applications.
On the calibration of astigmatism particle tracking velocimetry for microflows
Astigmatism particle tracking velocimetry (APTV) is a method to determine three components (3C) of the velocity field in a volume (3D) using a single camera. The depth position of the particles is
Three-dimensional particle tracking with subnanometer resolution using off-focus images.
A three-dimensional particle tracking algorithm based on microscope off-focus images is presented, enabling prediction of the measurement performance based on calibration data and the validity of the theoretical analysis is also experimentally confirmed.
Synthetic image generator for defocusing and astigmatic PIV/PTV
  • M. Rossi
  • Physics
    Measurement Science and Technology
  • 2019
This technical note introduces a synthetic image generator (SIG), referred to as MicroSIG, to be used for particle image/tracking velocimetry (PIV/PTV) analysis involving defocusing or astigmatic
On the effect of particle image intensity and image preprocessing on the depth of correlation in micro-PIV
The depth of correlation (DOC) is an experimental parameter, introduced to quantify the thickness of the measurement volume and thus the depth resolution in microscopic particle image velocimetry
Particle tracking velocimetry in three-dimensional flows
Hardware components for 3D PTV systems will be discussed, and a strict mathematical model of photogrammetric 3D coordinate determination, taking into account the different refractive indices in the optical path, will be presented.
Three-dimensional fluorescent particle tracking at micron-scale using a single camera
This article reports a new approach to track (x, y, z, t) coordinates of multiple fluorescent particles (diameter range 1–10 μm) simultaneously using a quantitative defocusing method. We find that
Three-dimensional particle imaging with a single camera
A new approach to the instantaneous three-dimensional mapping of flow fields is introduced. A single camera system uses defocusing in conjunction with a mask (three pin holes) embedded in the camera