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Updated: Jun 17, 2026
10:39
Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
The use of an improved diffraction grating interferometer.
Applied Optics
|January 16, 2010
Summary
Researchers converted a schlieren system into a Kraushaar interferometer using diffraction gratings. This enhanced optical instrument accurately measures surface pressures and flow fields around airfoils, showing good agreement with analytical data.
Area of Science:
- Optics and Fluid Dynamics
- Interferometry and Optical Instrumentation
Background:
- Conventional schlieren systems are effective for flow visualization.
- Diffraction gratings offer precise beam manipulation capabilities.
Purpose of the Study:
- To reconfigure a schlieren system into a Kraushaar interferometer.
- To evaluate the performance of this modified interferometer for aerodynamic measurements.
Main Methods:
- Addition of matched diffraction gratings to a conventional schlieren system.
- Summarization of the applicable optical theory.
- Investigation of factors influencing fringe and image quality.
Main Results:
- The modified system, a Kraushaar interferometer, demonstrated effective beam splitting and recombination.
- Optical quality of diffraction gratings was not limiting; platform isolation is crucial.
- Successful measurement of surface pressures and flow fields around 2D airfoils.
Conclusions:
- The diffraction grating Kraushaar interferometer is a viable tool for aerodynamic analysis.
- Experimental data closely matches analytical calculations, validating the instrument's accuracy.
- Proper optical platform isolation is essential for optimal performance.
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