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Abstract Meta‐devices have attracted great interest due to the unprecedented capabilities of manipulating wavefronts. Complex‐amplitude hologram can provide high‐quality images that can be free of ghost images and undesired diffraction orders. However, conventional meta‐holograms usually operate at a single band with phase‐only modulation. Here, a reflective 2‐bit meta‐hologram is proposed to operate with independent complex‐amplitude modulations at two frequency bands. The high‐efficiency meta‐atom is composed of a top perforated metallic layer, on which two C‐shape split ring resonators (CSRRs) are located in the centers of a circular hole and an annular slot. By tuning the sizes of the two CSRRs, dual‐band 2‐bit phase modulations can be individually achieved, while the amplitude profile can be continuously tailored at each band by rotating the corresponding CSRR without affecting the phase responses. Based on this emerging meta‐atom, a dual‐band bifocal metalens is demonstrated numerically and a bispectral meta‐hologram is validated both numerically and experimentally at two widely used communication bands. The proposed method features all desirable advantages of the coding metasurfaces with extra degrees of freedom by providing independent frequency control and amplitude modulation, which can provide great opportunities in multifunctional applications with enhanced performance and boosted information capacity.
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Photonic Integrated Full-Color Holograms for Visible Light Based on Meta-Waveguides
We experimentally demonstrate photonic integrated visible full-color meta-holograms based on guided wave-driven metasurfaces with complete phase-and-amplitude control capability. Our lightweight and compact meta-holograms can be potentially used for virtual/augmented/mixed reality near-eye displays.
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- Award ID(s):
- 2047446
- PAR ID:
- 10415979
- Date Published:
- Journal Name:
- 2022 Conference on Lasers and Electro-Optics (CLEO)
- Page Range / eLocation ID:
- FM2H.1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/CLEO_QELS.2022.FM2H.1
