Jove
Visualize
Contact Us

Related Concept Videos

Electronic Distance Measuring Instruments01:30

Electronic Distance Measuring Instruments

Electronic Distance Measuring Instruments (EDMs) are essential tools in modern surveying, offering precise distance measurements by emitting electromagnetic signals and calculating the time required for these signals to travel to a target and return. Two primary types of signals are used in EDMs — light waves and microwaves — each suited to specific environmental and distance requirements. Light-wave-based EDMs utilize either infrared or laser light, providing high accuracy over short distances...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Confocal imaging of a stratified medium.

Applied optics·2010
Same author

Fabrication and characterization of a planar gradient-index, plasma-enhanced chemical vapor deposition lens.

Applied optics·2008
Same author

Linear phase imaging using differential interference contrast microscopy.

Journal of microscopy·2004
Same author

Feature extraction of chromosomes from 3-D confocal microscope images.

IEEE transactions on bio-medical engineering·2001
Same author

Using the Hilbert transform for 3D visualization of differential interference contrast microscope images.

Journal of microscopy·2000
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Video

Updated: Jul 6, 2026

The Frequency Domain Thermoreflectance Technique for Thermal Property Measurements
09:10

The Frequency Domain Thermoreflectance Technique for Thermal Property Measurements

Published on: December 5, 2025

Minimum theoretical requirements for three-dimensional scanning-laser Doppler anemometry.

P J Cronin1, C J Cogswell

  • 1Department of Physical Optics, School of Physics, University of Sydney, New South Wales 2006, Australia. paul@physics.usyd.edu.au

Applied Optics
|March 21, 2008
PubMed
Summary

Four beams are the minimum requirement for complete three-dimensional velocity reconstruction in laser Doppler anemometry (LDA) with a single detector. This study proves four beams are necessary, unlike three, for accurate 3D flow measurements.

More Related Videos

Automatic Laser-based Geometry Capture for Finite Element Analysis of Weld Beads
07:58

Automatic Laser-based Geometry Capture for Finite Element Analysis of Weld Beads

Published on: July 25, 2025

Simultaneous Measurement of Turbulence and Particle Kinematics Using Flow Imaging Techniques
10:53

Simultaneous Measurement of Turbulence and Particle Kinematics Using Flow Imaging Techniques

Published on: March 12, 2019

Related Experiment Videos

Last Updated: Jul 6, 2026

The Frequency Domain Thermoreflectance Technique for Thermal Property Measurements
09:10

The Frequency Domain Thermoreflectance Technique for Thermal Property Measurements

Published on: December 5, 2025

Automatic Laser-based Geometry Capture for Finite Element Analysis of Weld Beads
07:58

Automatic Laser-based Geometry Capture for Finite Element Analysis of Weld Beads

Published on: July 25, 2025

Simultaneous Measurement of Turbulence and Particle Kinematics Using Flow Imaging Techniques
10:53

Simultaneous Measurement of Turbulence and Particle Kinematics Using Flow Imaging Techniques

Published on: March 12, 2019

Area of Science:

  • Fluid Dynamics
  • Optical Measurement Techniques
  • Laser Physics

Background:

  • Laser Doppler Anemometry (LDA) is a non-intrusive technique for measuring fluid velocity.
  • Accurate three-dimensional velocity reconstruction is crucial for understanding complex flow fields.
  • Single-detector LDA systems offer practical advantages but pose challenges for multi-dimensional measurements.

Purpose of the Study:

  • To determine the minimum number of intersecting beams for complete 3D velocity reconstruction in single-detector LDA.
  • To provide definitive arguments for the necessity of four beams over three for full velocity vector determination.
  • To identify optimal beam arrangements for enhanced signal quality and robustness.

Main Methods:

  • Derivation of general expressions for detected signals in LDA systems.
  • Matrix analysis of signal expressions to assess velocity reconstruction capabilities.
  • Investigation of beam arrangements and their impact on signal differentiation and alignment sensitivity.

Main Results:

  • Three beams are insufficient for complete 3D velocity reconstruction, regardless of physical arrangement.
  • Four beams are identified as the minimum requirement for unambiguous and complete 3D velocity measurement.
  • Optimal four-beam configurations are determined for improved signal separation and tolerance to optical errors.

Conclusions:

  • Complete 3D velocity reconstruction in LDA necessitates a minimum of four intersecting beams.
  • The study validates the superiority of four beams for accurate flow diagnostics.
  • Scanning methods for velocity component determination are presented as mechanically simpler and enable velocity imaging.