@article{kudenov_pantalone_yang_2020, title={Dual-beam potassium Voigt filter for atomic line imaging}, volume={59}, ISSN={["2155-3165"]}, DOI={10.1364/AO.393649}, abstractNote={Spectrally narrowband imaging in remote sensing applications can be advantageous for detecting atomic emission features. This is especially useful in detecting specific constituents within rocket plumes, which are challenging to discern from naturally occurring sunglints. In this paper, we demonstrate a dual-beam technique, implemented with a Wollaston prism, for calibrating a Voigt magneto-optical filter for a linear polarizer's finite extinction ratio, as well as optical misalignment between the linear polarizers' transmission axes. Such a strategy would be key towards expanding the filter's field of view while maintaining its classification capabilities. Validation of the potassium Voigt filter is demonstrated using the simulation tool ElecSus in combination with a potassium hollow cathode lamp. RMS error between the filter's temperature response and that of the simulation was approximately 2%. We then demonstrate the detection of a potassium model rocket motor outdoors alongside a sunglint. Results indicate a 20-fold increase in contrast when using our dual-beam calibration strategy.}, number={17}, journal={APPLIED OPTICS}, author={Kudenov, Michael W. and Pantalone, Brett and Yang, Ruonan}, year={2020}, month={Jun}, pages={5282–5289} }
 @article{kudenov_pantalone_2019, title={Direct correlation spectrometer using polarized light}, volume={11132}, ISSN={["1996-756X"]}, DOI={10.1117/12.2530056}, abstractNote={Measuring a target’s radial velocity is usually achieved using high-resolution spectroscopy; however, higher signal to noise ratios can be obtained using direct correlation spectrometers (DCSs). In our system, a liquid crystal spatial light modulator serves as the mask against which the incident spectrum is correlated, and the polarization is controlled to enable both in- and out-of-band light to be captured simultaneously. This offers enhanced performance against atmospheric scintillation and may also enable single-shot radial velocity measurements. In this paper, we describe the design and implementation of our polarization-DCS and experimental validation is performed by acquiring radial velocity measurements of Venus.}, journal={POLARIZATION SCIENCE AND REMOTE SENSING IX}, author={Kudenov, Michael W. and Pantalone, Brett}, year={2019} }
 @article{kudenov_pantalone_2019, title={Dual-beam cross-correlation spectrometer for radial velocity measurements}, volume={58}, ISSN={["2155-3165"]}, DOI={10.1364/AO.58.009310}, abstractNote={Measuring the radial velocity of an object can be achieved by quantifying the Doppler shift of Fraunhofer lines. Measurements are typically made using high-resolution conventional spectroscopy, in which the Doppler shift is calculated numerically on a computer. An alternative technique includes cross-correlation spectroscopy, which performs an optical correlation of the incident spectrum against a reference spectrum embedded in the instrument. Many existing correlation spectrometers leverage a chrome mask and obtain a single beam measurement, making the sensors more sensitive to atmospheric turbulence without moving parts. In this paper, we present a static dual-beam polarization-based technique for acquiring cross-correlation spectra that is insensitive to atmospheric turbulence and contains no moving parts. The instrument is based on acquiring light both inside and outside of the solar Fraunhofer lines using a twisted nematic liquid-crystal spatial light modulator. Correlation spectra can be calculated as a ratio of these two components. A model of the dual-beam cross-correlation spectrometer is presented and subsequently validated with experimental observations of Venus. Radial velocity accuracies, as calculated against reference ephemerides, yielded an absolute error less than 0.24%.}, number={33}, journal={APPLIED OPTICS}, author={Kudenov, Michael W. and Pantalone, Brett}, year={2019}, month={Nov}, pages={9310–9317} }
 @article{pantalone_kudenov_2017, title={Fraunhofer line optical correlator for improvement of initial orbit determination}, volume={10407}, ISBN={["978-1-5106-1271-6"]}, ISSN={["1996-756X"]}, DOI={10.1117/12.2274804}, abstractNote={The design of a Fraunhofer line optical correlator is detailed. The instrument described herein correlates a reflected solar spectrum against multiple Fraunhofer absorption lines to estimate the radial velocity of the reflecting body. By using a spatial light modulator (SLM) as a photomask for known solar absorption lines in the visible spectrum, the ratio of Doppler shifted solar energy to the total received energy can be calculated. Although the reflected light from targets in high orbit is weak, signal-to-noise ratio (SNR) is enhanced by the measurement of multiple Fraunhofer lines in a single snapshot image. Simulations indicate that prediction of orbital parameters is improved by incorporation of this velocity information, and in some cases the number of line-of-sight measurements can be reduced from three to two.}, journal={POLARIZATION SCIENCE AND REMOTE SENSING VIII}, author={Pantalone, Brett A. and Kudenov, Michael W.}, year={2017} }
 @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} }