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Updated: Jul 6, 2026
10:39
Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
Ray and van cittert-zernike characterization of spatial coherence.
Applied Optics
|March 22, 2008
Summary
This study introduces a ray-tracing method to measure spatial coherence in projection systems. A new metric, root-mean-square angular ray spread, helps characterize local coherence properties.
Area of Science:
- Optical engineering
- Coherence theory
Background:
- Spatial coherence is crucial for projection system performance.
- Characterizing coherence in condensers is complex.
Purpose of the Study:
- To develop a practical method for assessing spatial coherence in projection system condensers.
- To establish a relationship between coherence and pupil illumination.
- To propose a new metric for local coherence properties.
Main Methods:
- Utilized a ray-tracing methodology to determine the modulus of the coherence function.
- Developed a rule of thumb for estimating coherence function modulus.
- Analyzed the relationship between coherence function modulus and pupil-filling factor under uniform illumination.
Main Results:
- A ray-tracing approach was established to quantify spatial coherence.
- A rule of thumb was provided for estimating coherence.
- The modulus of the coherence function was related to the pupil-filling factor for uniform illumination.
Conclusions:
- The root-mean-square of the angular ray spread is a suitable metric for characterizing local coherence.
- The developed methods offer practical tools for analyzing coherence in projection systems.
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