* Equal contribution · † Corresponding authors
Obstructions such as raindrops, fences, or dust degrade images, especially when cleaning is infeasible. Conventional approaches use bulky compound-lens arrays or computational inpainting, compromising compactness or fidelity. Metalenses promise compact imaging, but achieving both broadband and obstruction-free imaging remains challenging because a metalens cannot simultaneously focus distant scenes and defocus nearby occlusions across a broadband spectrum.
We introduce a de-occluding broadband metalens that suppresses obstructions while enabling broadband imaging with an optimized metalens design map. A multi-band spectral filter divides each color channel into pass and stop bands: far-scene light is focused through the pass bands, while focused light from nearby obstructions shifts into the stop bands and is rejected. A neural network further enhances the captured image.
Source-verified optical captures show how the proposed system suppresses nearby obstructions and preserves evidence for downstream vision.
The obstruction itself is shown first. The hyperbolic lens is designed at 532 nm, while the broadband baseline retains near-depth dirt. Our result approaches the unobstructed reference.
Each optical input is paired with its detector prediction. The digital reference is paired with the dataset ground-truth annotation.
Polyp-segmentation predictions are compared under identical scene content and obstruction conditions.
Semantic labels remain spatially coherent when the proposed optics suppress the near-depth obstruction before inference.
All panels are source-verified crops from Figures 5 and 6; no generated or inpainted content is used.
Because our method operates in a single shot, it naturally extends to video imaging.
For a diffractive lens, a coupled change in source wavelength and depth can produce nearly invariant PSFs.
On small screens, scroll horizontally to inspect the complete focal-intensity map.
For λ > λd, chromatic phase mismatch produces a focal-front shift relative to the design wavelength.
On small screens, scroll horizontally to inspect the complete recap figure.
Stack the monochromatic far-depth PSFs across wavelength to form the x–λ scan.
The visible-light SiNx metalens was fabricated, and its far- and near-depth PSFs were measured from 430 to 645 nm in 5 nm steps.
| Method | PSNR ↑ | SSIM ↑ | LPIPS ↓ |
|---|---|---|---|
| Hyperbolic | 20.72 | 0.6640 | 0.5402 |
| Broadband | 22.16 | 0.6938 | 0.5203 |
| Ours | 25.39 | 0.8016 | 0.4052 |
24.15 FPS network inference at FP16, batch 1, 512 × 512 on an RTX 6000 Ada.
Each pair reports unobstructed / obstructed performance. Digital GT provides the reference image and label, not a comparable optical-method score.
| Method | Unobstructed to obstructed | Change |
|---|---|---|
| Hyperbolic | 21.75% → 3.50% | −18.25 pp |
| Broadband | 10.66% → 2.92% | −7.74 pp |
| Ours | 24.27% → 17.04% | −7.23 pp |
| Method | Unobstructed to obstructed | Change |
|---|---|---|
| Hyperbolic | 80.80% → 34.72% | −46.08 pp |
| Broadband | 81.99% → 59.50% | −22.49 pp |
| Ours | 83.56% → 83.17% | −0.39 pp |
| Method | Unobstructed to obstructed | Change |
|---|---|---|
| Hyperbolic | 60.01% → 46.66% | −13.35 pp |
| Broadband | 59.42% → 46.01% | −13.41 pp |
| Ours | 70.80% → 67.01% | −3.79 pp |
@article{yoon2026deoccluding,
title = {De-occluding broadband metalens},
author = {Yoon, Seungwoo and Kang, Dohyun and Choi, Eunsue and Lee, Sohyun and Kim, Seoyeon and Choi, Minho and Heo, Hyeonsu and Shin, Dong-Ha and Kwak, Suha and Majumdar, Arka and Rho, Junsuk and Baek, Seung-Hwan},
journal = {Nature Communications},
year = {2026},
doi = {10.1038/s41467-026-76606-0},
url = {https://doi.org/10.1038/s41467-026-76606-0}
}