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Updated: Jun 6, 2026
10:39
Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
Diffraction effects in the radiometry of coherent beams.
Applied Optics
|November 19, 2010
Summary
Accurate radiometry needs a contained optical beam. Analysis reveals diffraction rings form, impacting the smallest calibratable detector radius.
Area of Science:
- Optical physics
- Metrology
Background:
- High-accuracy radiometry demands precise control over optical beam characteristics.
- Ensuring all light falls within the detector's aperture is critical for calibration.
Purpose of the Study:
- To analyze a common optical setup for preparing beams for radiometry.
- To investigate the impact of diffraction on beam profiles and calibration limits.
Main Methods:
- Calculation of the beam profile for a specific optical configuration.
- Analysis of far-field diffraction patterns.
Main Results:
- Diffraction rings are observed in the far field.
- The irradiance at the edge of the limiting aperture is zero.
- A method to determine the maximum calibratable detector radius is derived.
Conclusions:
- The presence of diffraction rings limits the applicability of simple beam models.
- Accurate determination of the beam profile is essential for defining calibration limits in radiometry.
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