@article{maione_baldridge_kudenov_2019, title={Microbolometer with a multi-aperture polymer thin-film array for neural-network-based target identification}, volume={58}, ISSN={["2155-3165"]}, DOI={10.1364/AO.58.007285}, abstractNote={Infrared imaging spectrometers are frequently used for detecting chemicals at standoff distances. Cost, size, and sensitivity are common tradeoffs in this regime, particularly when deploying infrared imaging arrays. In this work, we develop and characterize an infrared snapshot computational imaging spectrometer that leverages a multi-aperture filtered design. A theoretical model is developed, describing the multiplexed encoding technique. The experimental system is then described, including filter optimization and fabrication. Finally, the performance of the system is tested, leveraging a neural-network-based calibration approach, for various indoor and outdoor detection scenarios involving liquid contaminants. The results of our testing demonstrate that the system can detect room-temperature liquid contaminants under cold sky downwelling radiance conditions. We achieve a false positive rate (FPR) of 0.12% at a true positive rate (TPR) of 95% for silicon oil on sand at 18°C and a FPR of 2% at a TPR of 95% for silicon oil on various substrates at 23°C. Results support the efficacy of using uncooled polymer absorption filters for infrared imaging liquid contaminant detectors.}, number={27}, journal={APPLIED OPTICS}, author={Maione, Bryan D. and Baldridge, Christopher and Kudenov, Michael W.}, year={2019}, month={Sep}, pages={7285–7297} }
 @article{maione_brickson_escuti_kudenov_2017, title={Snapshot imaging spectrometry with a heterodyned Savart plate interferometer}, volume={56}, ISSN={["1560-2303"]}, DOI={10.1117/1.oe.56.8.081806}, abstractNote={Imaging spectrometers are frequently used in remote sensing for their increased target discrimination capabilities over conventional imaging. Increasing the spectral resolution of these sensors further enables the system’s ability to discriminate certain targets and adds the potential for monitoring narrow-line spectral features. We describe a high spectral resolution (Δλ=1.1  nm full-width at half maximum) snapshot imaging spectrometer capable of distinguishing two narrowly separated bands in the red-visible spectrum. A theoretical model is provided to detail the first polarization grating-based spatial heterodyning of a Savart plate interferometer. Following this discussion, the experimental conditions of the narrow-line imaging spectrometer (NLIS) are provided. Finally, calibration and target identification methods are applied and quantified. Ultimately it is demonstrated that in a full spectral acquisition the NLIS sensor is capable of less than 3.5% error in reconstruction. Additionally, it is demonstrated that neural networks provide greater than 99% reduction in crosstalk when compared to pseudoinversion and expectation maximization in single target identification.}, number={8}, journal={OPTICAL ENGINEERING}, author={Maione, Bryan and Brickson, Leandra and Escuti, Michael and Kudenov, Michael}, year={2017}, month={Aug} }
 @article{maione_brickson_kudenov_escuti_2016, title={Narrowband emission line imaging spectrometry using Savart plates}, volume={9853}, ISSN={["0277-786X"]}, DOI={10.1117/12.2224275}, abstractNote={Polarization spatial heterodyne interferometry (PSHI) allows for the development of compact, vibration insensitive, high spectral resolution sensors. Introducing the imaging qualities of a lenslet array extends the advantages of PSHI to imaging interferometers. The use of Savart plates enables a birefringent interferometer that obtains higher spectral resolution with fewer optical aberrations when compared to alternative designs. In this paper, we describe the design, construction, calibration and validation of a narrowband emission line imaging spectrometer (NELIS), based on Savart plates and liquid crystal polarization gratings, along with its associated theoretical model. This sensor is advantageous for spectral imaging in the areas of remote sensing, biomedical imaging and machine vision.}, journal={POLARIZATION: MEASUREMENT, ANALYSIS, AND REMOTE SENSING XII}, author={Maione, Bryan and Brickson, Leandra and Kudenov, Michael and Escuti, Michael}, year={2016} }
 @article{maione_luo_miskiewicz_escuti_kudenov_2016, title={Spatially heterodyned snapshot imaging spectrometer}, volume={55}, ISSN={["2155-3165"]}, DOI={10.1364/ao.55.008667}, abstractNote={Snapshot hyperspectral imaging Fourier transform (SHIFT) spectrometers are a promising technology in optical detection and target identification. For any imaging spectrometer, spatial, spectral, and temporal resolution, along with form factor, power consumption, and computational complexity are often the design considerations for a desired application. Motivated by the need for high spectral resolution systems, capable of real-time implementation, we demonstrate improvements to the spectral resolution and computation trade-space. In this paper, we discuss the implementation of spatial heterodyning, using polarization gratings, to improve the spectral resolution trade space of a SHIFT spectrometer. Additionally, we employ neural networks to reduce the computational complexity required for data reduction, as appropriate for real-time imaging applications. Ultimately, with this method we demonstrate an 87% decrease in processing steps when compared to Fourier techniques. Additionally, we show an 80% reduction in spectral reconstruction error and a 30% increase in spatial fidelity when compared to linear operator techniques.}, number={31}, journal={APPLIED OPTICS}, author={Maione, Bryan D. and Luo, David and Miskiewicz, Matthew and Escuti, Michael and Kudenov, Michael W.}, year={2016}, month={Nov}, pages={8667–8675} }
 @article{kudenov_roy_pantalone_maione_2015, title={Ultraspectral Imaging and the Snapshot Advantage}, volume={9467}, ISSN={["1996-756X"]}, DOI={10.1117/12.2176980}, abstractNote={Ultraspectral sensing has been investigated as a way to resolve terrestrial chemical fluorescence within solar Fraunhofer lines. Referred to as Fraunhofer Line Discriminators (FLDs), these sensors attempt to measure "band filling" of terrestrial fluorescence within these naturally dark regions of the spectrum. However, the method has challenging signal to noise ratio limitations due to the low fluorescence emission signal of the target, which is exacerbated by the high spectral resolution required by the sensor (<0.1 nm). To now, many Fraunhofer line discriminators have been scanning sensors; either pushbroom or whiskbroom, which require temporal and/or spatial scanning to acquire an image. In this paper, we attempt to quantify the snapshot throughput advantage in ultraspectral imaging for FLD. This is followed by preliminary results of our snapshot FLD sensor. The system has a spatial resolution of 280x280 pixels and a spectral resolving power of approximately 10,000 at a 658 nm operating wavelength.}, journal={MICRO- AND NANOTECHNOLOGY SENSORS, SYSTEMS, AND APPLICATIONS VII}, author={Kudenov, Michael W. and Roy, Subharup Gupta and Pantalone, Brett and Maione, Bryan}, year={2015} }
 @article{maione_luo_kudenov_escuti_miskiewicz_2014, title={Birefringent snapshot imaging spatial heterodyne spectrometer}, volume={9099}, ISSN={["1996-756X"]}, DOI={10.1117/12.2049726}, abstractNote={High speed spectral imaging is useful for a variety of tasks spanning industrial monitoring, target detection, and chemical identification. To better meet these needs, compact hyperspectral imaging instrumentation, capable of high spectral resolution and real-time data acquisition and processing, are required. In this paper, we describe the first snapshot imaging spatial heterodyne Fourier transform spectrometer based on birefringent crystals and polarization gratings. This includes details about its architecture, as well as our preliminary proof of concept. Finally, we discuss details related to the calibration of the sensor, including our preliminary investigations into high speed data reconstruction and calibration using neural networks. With such an approach, it may be feasible to reconstruct and calibrate an entire interferogram cube in one step with minimal Fast Fourier Transform (FFT) processing.}, journal={POLARIZATION: MEASUREMENT, ANALYSIS, AND REMOTE SENSING XI}, author={Maione, Bryan D. and Luo, David A. and Kudenov, Michael W. and Escuti, Michael J. and Miskiewicz, Matthew N.}, year={2014} }