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Sub-wavelength diffractive meta-optics have emerged as a versatile platform to manipulate light fields at will, due to their ultra-small form factor and flexible multifunctionalities. However, miniaturization and multimodality are typically compromised by a reduction in imaging performance; thus, meta-optics often yield lower resolution and stronger aberration compared to traditional refractive optics. Concurrently, computational approaches have become popular to improve the image quality of traditional cameras and exceed limitations posed by refractive lenses. This in turn often comes at the expense of higher power and latency, and such systems are typically limited by the availability of certain refractive optics. Limitations in both fields have thus sparked cross-disciplinary efforts to not only overcome these roadblocks but also to go beyond and provide synergistic meta-optical–digital solutions that surpass the potential of the individual components. For instance, an application-specific meta-optical frontend can preprocess the light field of a scene and focus it onto the sensor with a desired encoding, which can either ease the computational load on the digital backend or can intentionally alleviate certain meta-optical aberrations. In this review, we introduce the fundamentals, summarize the development of meta-optical computational imaging, focus on latest advancements that redefine the current state of the art, and give a perspective on research directions that leverage the full potential of sub-wavelength photonic platforms in imaging and sensing applications. The current advancement of meta-optics and recent investments by foundries and technology partners have the potential to provide synergistic future solutions for highly efficient, compact, and low-power imaging systems.
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Large field-of-view thermal imaging via all-silicon meta-optics
A broad range of imaging and sensing technologies in the infrared require large field-of-view (FoV) operation. To achieve this, traditional refractive systems often employ multiple elements to compensate for aberrations, which leads to excess size, weight, and cost. For many applications, including night vision eye-wear, air-borne surveillance, and autonomous navigation for unmanned aerial vehicles, size and weight are highly constrained. Sub-wavelength diffractive optics, also known as meta-optics, can dramatically reduce the size, weight, and cost of these imaging systems, as meta-optics are significantly thinner and lighter than traditional refractive lenses. Here, we demonstrate 80° FoV thermal imaging in the long-wavelength infrared regime (8–12 µm) using an all-silicon meta-optic with an entrance aperture and lens focal length of 1 cm.
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- PAR ID:
- 10437988
- Publisher / Repository:
- Optica
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 62
- Issue:
- 20
- ISSN:
- 1559-128X
- Page Range / eLocation ID:
- 5467
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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