Design and validation of a holographic particle counter

Georg Brunnhofer, Alexander Bergmann, Andreas Klug, Martin Kraft

Research output: Contribution to journalArticleResearchpeer-review


An in-line holographic particle counter concept is presented and validated where multiple micrometer sized particles are detected in a three dimensional sampling volume, all at once. The proposed Particle Imaging Unit is capable of detecting holograms of particles which sizes are in the lower µm-range. The detection and counting principle is based on common image processing techniques using a customized Hough Transform with a result directly relating to the particle number concentration in the recorded sampling volume. The proposed counting unit is mounted ontop of a Condensation Nucleus Magnifier for comparison with a commercial TSI-3775 Condensation Particle Counter (CPC). The concept does not only allow for a precise in-situ determination of low particle number concentrations but also enables easy upscaling to higher particle densities (e.g., > 30.000 ccm# ) through its linear expandability and option of cascading. The impact of coincidence at higher particle densities is shown and two coincidence correction approaches are presented where, at last, its analogy to the coincidence correction methods used in state-of-the-art CPCs is identified.

Original languageEnglish
Article number4899
JournalSensors (Switzerland)
Issue number22
Publication statusPublished - 2 Nov 2019


  • Coincidence correction
  • Condensation Particle Counter
  • Hough Transform
  • In-line holography

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Atomic and Molecular Physics, and Optics
  • Instrumentation
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Design and validation of a holographic particle counter'. Together they form a unique fingerprint.

  • Cite this