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Updated: Jul 5, 2026
10:39
Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
Beam splitting of low-contrast binary gratings under second Bragg angle incidence
Jiangjun Zheng1, Changhe Zhou, Bo Wang
1Information Optics Lab, Shanghai Institute of Optics and Fine Mechanics, Academia Sinica, Shanghai, China.
Summary
Researchers explored beam splitting using low-contrast gratings at the second Bragg angle. They achieved high efficiency for 1x2 beam splitters, concentrating energy into specific diffraction orders.
Area of Science:
- Optics and Photonics
- Diffractive Optics
Background:
- Beam splitting is crucial for optical systems.
- Diffractive gratings offer miniaturization and novel functionalities.
Purpose of the Study:
- Investigate beam splitting with low-contrast gratings at the second Bragg angle.
- Develop high-efficiency grating-based beam splitters.
Main Methods:
- Analysis of three transmitted propagating orders.
- Simplified modal approach for design conditions.
- Rigorous coupled-wave analysis for verification.
Main Results:
- Achieved ~90% energy concentration in the -2nd transmitted order.
- Demonstrated 1x2 beam splitters with >90% total efficiency.
- Showcased a 1x3 beam splitter and polarization-selective potential.
Conclusions:
- The second Bragg angle incidence enables efficient beam splitting with low-contrast gratings.
- This method is effective for designing high-efficiency beam splitters and polarization-selective elements.
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