Broadband imaging with one planar diffractive lens
Abstract
We demonstrate imaging over the visible band using a single planar diffractive lens. This is enabled via multi-level diffractive optics that is designed to focus over a broad wavelength range, which we refer to as an achromatic diffractive lens (ADL). We designed, fabricated and characterized two ADLs with numerical apertures of 0.05 and 0.18. Diffraction-limited focusing is demonstrated for the NA = 0.05 lens with measured focusing efficiency of over 40% across the entire visible spectrum (450 nm to 750 nm). We characterized the lenses with a monochromatic and a color CMOS sensor, and demonstrated video imaging under natural sunlight and other broadband illumination conditions. We use rigorous electromagnetic simulations to emphasize that ADLs can achieve high NA (0.9) and large operating bandwidth (300 nm in the visible spectrum), a combination of metrics that have so far eluded other flat-lens technologies such as metalenses. These planar diffractive lenses can be cost-effectively manufactured over large areas and thereby, can enable the wide adoption of flat, low-cost lenses for a variety of imaging applications.
Additional Information
© 2018 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Received: 12 September 2017; Accepted: 31 January 2018; Published online: 12 February 2018. We thank Brad Sohnlein and Husain Imam from NKT Photonics for assistance with the super-continuum source. We thank Ganghun Kim for help with blind deconvolution of the Air Force target images. We also thank Patrick Clifford (http://www.pcedits.com) for editing the supplementary videos. We gratefully acknowledge support from a DOE Sunshot Grant, EE0005959, a NASA Early Stage Innovations Grant, NNX14AB13G, and the Utah Science Technology and Research (USTAR) Initiative. Author Contributions: N.M. assembled the optical system, performed all experiments and analyzed the data. M.M. fabricated the lenses, characterized their geometry, performed all experiments and analyzed the data. B.S. performed the FDTD simulations. R.M. conceived and designed the experiments. All authors edited the manuscript. P.W. and R.M. wrote the flat-lens design software. The authors declare no competing interests.Attached Files
Published - s41598-018-21169-4.pdf
Supplemental Material - 41598_2018_21169_MOESM1_ESM.mov
Supplemental Material - 41598_2018_21169_MOESM2_ESM.mov
Supplemental Material - 41598_2018_21169_MOESM3_ESM.pdf
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Additional details
- PMCID
- PMC5809505
- Eprint ID
- 84893
- Resolver ID
- CaltechAUTHORS:20180220-124340472
- EE0005959
- Department of Energy (DOE)
- NNX14AB13G
- NASA
- Utah Science Technology and Research (USTAR) Initiative
- Created
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2018-02-21Created from EPrint's datestamp field
- Updated
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2022-03-17Created from EPrint's last_modified field