| Autor: |
Xue Dongbai, Dun Xiong, Wei Zeyong, Li DongDong, Zhu Jingyuan, Zhang Zhanyi, Wang Zhanshan, Cheng Xinbin |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
Nanophotonics, Vol 13, Iss 8, Pp 1379-1385 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
2192-8614 |
| DOI: |
10.1515/nanoph-2023-0719 |
| Popis: |
Collimated flat-top beam shapers primarily consisting of freeform lenses have a wide range of applications and pose challenges in terms of processing and integration when the diameter is less than millimeters. Metasurfaces represent a promising solution to planarize optics, can mimic any surface curvature without additional fabrication difficulty, and are suitable for flat-top optics. The conventional metasurface design approach relies on imparting the required phase using meta-atoms and encounters challenges in amplitude modulation due to near-field coupling and varying transmittances among meta-atoms with different phases, making the design of flat-top beam shapers difficult. In this paper, we propose a complex-amplitude constraint Gerchberg–Saxton algorithm for designing a collimated flat-top beam shaper metasurface doublet, which avoids the influence of strong near-field coupling on the amplitude distribution and simultaneously considers the amplitude-phase characteristics of the meta-atoms. A collimated flat-top beam with exceptional homogeneity U p of approximately 0.01, a wavefront error less than 0.1λ, and a transmittance higher than 86 % is experimentally obtained, comparable to commercial products based on freeform lenses. A collimated flat-top beam shaper metasurface doublet for generating flat-top beam is introduced, promoting efficient integration with laser systems. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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