Stereoscopic imaging of dusty plasmas

Abstract

The fundamentals of stereoscopy and their application to dusty plasmas are described. It is shown that stereoscopic methods allow us to measure the three-dimensional particle positions and trajectories with high spatial and temporal resolution. The underlying technical implications are presented and requirements and limitations are discussed. The stereoscopic method is demonstrated for dust particles in dust-density waves under microgravity conditions.

Layered structures in extended dust clouds under microgravity

“…This huge number of particles demands efficient calculations and carefully coded algorithms to keep the computation time as low as possible. Algorithms [22][23][24] that perform well with a particle number N d ( 10 4 cannot be applied in this case, as the time or/and the memory usage would be too exhaustive and many erroneous detections would impact the analysis quality.…”

Three-Dimensional Reconstruction of Individual Particles in Dense Dust Clouds: Benchmarking Camera Orientations and Reconstruction Algorithms

“…As the particles are typically micrometer-sized and separated by some hundred micrometers, a dusty plasma that occupies several cubic centimeters is optically thin. This allows viewing of individual dust particles [6][7][8]. Nevertheless, from a single viewing direction, mutual occlusion of particles is a frequent phenomenon.…”

“…In recent years, two main approaches have been used to determine particle trajectories in many-particle structures: Triangulation and, more recently, iterative reconstruction [ 9 , 10 , 11 ]. In this paper, both approaches will be benchmarked in order to help other experimenters in choosing and building appropriate setups for their experiments.…”

Application of particle image velocimetry to dusty plasma systems

“…2013; Melzer et al. 2016). For dusty plasmas with higher number densities, where it is difficult to identify or track individual particles, particle image velocimetry (PIV) techniques can be used to measure the motion of groups of particles (Thomas Jr 1999; Thomas Jr, Williams & Silver 2004; Williams 2011; Williams et al.…”

“…From these measurements of particle transport, it is then possible to gain insight into the underlying physics that governs the behaviour of the dust component, as well as the state of the background plasma. For systems with sufficiently low number densities, particle tracking velocimetry (PTV) techniques are often employed to measure the motion of individual dust grains (Feng, Goree & Liu 2007;Ticos et al 2013;Melzer et al 2016). For dusty plasmas with higher number densities, where it is difficult to identify or track individual particles, particle image velocimetry (PIV) techniques can be used to measure the motion of groups of particles (Thomas Jr 1999;Thomas Jr, Williams & Silver 2004;Williams 2011;Williams et al 2012).…”