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High-precision phase retrieval in mode-division multiplexing systems using extended Nijboer-Zernike polynomials
Optics Express
|May 4, 2026
Summary
A new reference-free optical field measurement method using extended Nijboer-Zernike (ENZ) polynomials improves phase reconstruction accuracy for complex spatial modes in mode-division multiplexing (MDM) systems.
Area of Science:
- Photonics and Optical Engineering
- Optical Communications
- Metrology
Background:
- Accurate optical field characterization is crucial for mode-division multiplexing (MDM) systems.
- Conventional phase measurement techniques like off-axis holography are bulky and lack robustness for complex spatial modes.
Purpose of the Study:
- To propose and validate a novel reference-free optical field measurement method.
- To enhance phase reconstruction accuracy and robustness for complex optical modes.
Main Methods:
- Development of a reference-free phase retrieval system utilizing extended Nijboer-Zernike (ENZ) polynomials.
- Reconstruction of complex pupil-plane fields from multi-focal plane intensity measurements at 1550 nm.
- Validation using various modes including LP and orbital angular momentum (OAM) modes.
Main Results:
- The ENZ method significantly reduced phase root mean square error (Phase RMSE) compared to off-axis holography, with improvements up to 75% for OAM modes.
- Demonstrated stable and reliable phase reconstruction performance under varying noise levels and experimental parameters.
- Achieved overall improvements of 44%-75% in phase reconstruction accuracy.
Conclusions:
- The proposed ENZ-based method offers a robust and scalable solution for high-precision optical field measurement.
- This technique enhances accuracy and reduces fluctuations in phase reconstruction for multimode optical communication systems.
- The reference-free approach simplifies experimental setups and improves performance for complex spatial modes.
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