Related Experiment Video
Updated: Jun 7, 2026
07:27
Quantifying Microorganisms at Low Concentrations Using Digital Holographic Microscopy (DHM)
Published on: November 1, 2017
High speed digital holography for density and fluctuation measurements (invited)
C E Thomas1, L R Baylor, S K Combs
1Third Dimension Technologies LLC, 3601 Bluff Point Drive, Knoxville, Tennessee 37920, USA. thomasce2@att.net
The Review of Scientific Instruments
|November 2, 2010
Summary
Digital holographic wavefront acquisition enables precise phase measurement for plasma diagnostics. This technique directly yields chord-integrated electron density using CO(2) lasers and high-speed cameras.
Area of Science:
- Electro-optics
- Plasma Physics
- Wavefront Sensing
Background:
- Digital holographic acquisition now enables precise wavefront phase measurement.
- Holographic techniques offer sub-wavelength accuracy with careful system design.
Purpose of the Study:
- To leverage advanced electro-optic techniques for plasma density diagnostics.
- To demonstrate the direct measurement of chord-integrated electron density.
Main Methods:
- Utilizing digital holographic wavefront acquisition to capture phase information.
- Employing CO(2) lasers and high-speed infrared cameras (up to 640x512 pixels, 40,000 fps).
- Applying plasma physics principles where refractive index is proportional to electron density at high frequencies.
Main Results:
- Holographic wavefront acquisition provides phase data at every measurement point with high accuracy.
- The phase measurement directly correlates to chord-integrated electron density.
- High-speed, high-resolution infrared cameras are suitable for this diagnostic.
Conclusions:
- Digital holography is a viable technique for precise plasma diagnostics.
- The method allows for direct, point-by-point measurement of integrated electron density.
- Advancements in electro-optics and camera technology facilitate these measurements.
