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Updated: Jun 19, 2026
10:39
Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
Summary
A new radiometric model simplifies calculating coherence properties of light fields. This model uses a radiance function, aligning with traditional radiometry principles for easier analysis of secondary sources.
Area of Science:
- Optics and Photonics
- Radiometry
- Coherence Theory
Background:
- Traditional radiometry models light propagation based on intensity.
- Calculating coherence properties (cross-spectral density, spectral degree of coherence) can be complex.
- Quasi-homogeneous sources are common in optical systems.
Purpose of the Study:
- To formulate a radiometric model for coherence propagation.
- To simplify the determination of coherence properties of optical fields.
- To establish a model consistent with established radiometry principles.
Main Methods:
- Formulation of a new radiometric model for coherence propagation.
- Utilizing a radiance function as a central element in the model.
- Applying the model to planar, secondary, quasi-homogeneous sources.
Main Results:
- The model simplifies the determination of cross-spectral density.
- The model simplifies the determination of the spectral degree of coherence.
- The radiance function satisfies the postulates of traditional radiometry.
Conclusions:
- The developed radiometric model effectively describes coherence propagation.
- The model offers a simplified approach to analyzing coherence properties of light fields from secondary sources.
- The model's consistency with traditional radiometry facilitates its application and understanding.
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