20 research outputs found
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 m) using an all-silicon meta-optic with an entrance aperture
and lens focal length of 1 cm.Comment: 9 pages, 5 figure
Coherent manipulation of nitrogen vacancy centers in 4H silicon carbide with resonant excitation
Silicon carbide (SiC) has become a key player in realization of scalable
quantum technologies due to its ability to host optically addressable spin
qubits and wafer-size samples. Here, we have demonstrated optically detected
magnetic resonance (ODMR) with resonant excitation, and clearly identified the
ground state energy levels of the NV centers in 4H-SiC. Coherent manipulation
of NV centers in SiC has been achieved with Rabi and Ramsey oscillations.
Finally, we show the successful generation and characterization of single
nitrogen vacancy (NV) center in SiC employing ion implantation. Our results are
highlighting the key role of NV centers in SiC as a potential candidate for
quantum information processing
Foveated Thermal Computational Imaging in the Wild Using All-Silicon Meta-Optics
Foveated imaging provides a better tradeoff between situational awareness
(field of view) and resolution and is critical in long-wavelength infrared
regimes because of the size, weight, power, and cost of thermal sensors. We
demonstrate computational foveated imaging by exploiting the ability of a
meta-optical frontend to discriminate between different polarization states and
a computational backend to reconstruct the captured image/video. The frontend
is a three-element optic: the first element which we call the "foveal" element
is a metalens that focuses s-polarized light at a distance of without
affecting the p-polarized light; the second element which we call the
"perifoveal" element is another metalens that focuses p-polarized light at a
distance of without affecting the s-polarized light. The third element is
a freely rotating polarizer that dynamically changes the mixing ratios between
the two polarization states. Both the foveal element (focal length = 150mm;
diameter = 75mm), and the perifoveal element (focal length = 25mm; diameter =
25mm) were fabricated as polarization-sensitive, all-silicon, meta surfaces
resulting in a large-aperture, 1:6 foveal expansion, thermal imaging
capability. A computational backend then utilizes a deep image prior to
separate the resultant multiplexed image or video into a foveated image
consisting of a high-resolution center and a lower-resolution large field of
view context. We build a first-of-its-kind prototype system and demonstrate 12
frames per second real-time, thermal, foveated image, and video capture in the
wild
Miniature color camera via flat hybrid meta-optics
The race for miniature color cameras using flat meta-optics has rapidly developed the end-to-end design framework using neural networks. Although a large body of work has shown the potential of this methodology, the reported performance is still limited due to fundamental limitations coming from meta-optics, mismatch between simulated and resultant experimental point spread functions, and calibration errors. Here, we use a HIL optics design methodology to solve these limitations and demonstrate a miniature color camera via flat hybrid meta-optics (refractive + meta-mask). The resulting camera achieves high-quality full-color imaging for a 5-mm aperture optics with a focal length of 5 mm. We observed a superior quality of the images captured by the hybrid meta-optical camera compared to a compound multi-lens optics of a mirrorless commercial camera.Peer reviewe