# General defocusing particle tracking: fundamentals and uncertainty assessment

@article{Barnkob2020GeneralDP, title={General defocusing particle tracking: fundamentals and uncertainty assessment}, author={Rune Barnkob and Massimiliano Rossi}, journal={Experiments in Fluids}, year={2020}, volume={61}, pages={1-14} }

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…

## 16 Citations

Defocus particle tracking: a comparison of methods based on model functions, cross-correlation, and neural networks

- Physics
- 2021

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

- Computer ScienceMeasurement Science and Technology
- 2020

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

- Physics, Computer Science
- 2021

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

- Physics
- 2021

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

- Computer Science
- 2019

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

- BiologyAIMS Biophysics
- 2021

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

- EngineeringMicrosystems & nanoengineering
- 2022

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.

- PhysicsPhysical review. E
- 2020

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

- Physics
- 2022

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.

- EngineeringBiomedical microdevices
- 2021

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.

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