Stéphane Lantagne

MRi dual-band MWIR imaging FTS

MR-i is an imaging version of the ABB Bomem MR Fourier-Transform spectroradiometer. This field instrument generates spectral datacubes in the MWIR and LWIR. It is designed to be sufficiently fast to acquire the spectral signatures of rapid events. The design is modular. The two output ports of the instrument can be populated with different combinations of detectors (imaging or not). For instance to measure over a broad spectral range, one output port can be equipped with a LWIR camera while the other port is equipped with a MWIR camera. No dichroics are used to split the bands, hence enhancing the sensitivity. Both ports can be equipped with cameras serving the same spectral range but set at different sensitivity levels in order to increase the measurement dynamic range and avoid saturation of bright parts of the scene while simultaneously obtaining good measurement of the faintest parts of the scene. Various telescope options are available for the input port. Overview of the instrument capabilities will be presented. Test results and results from field trials for a configuration with two MWIR cameras will be presented. That specific system is dedicated to the characterization of airborne targets. The two MWIR cameras are used to expand the dynamic range of the instrument and simultaneously measure the spectral signature of the cold background and of the warmest elements of the scene (flares, jet engines exhausts, etc.).

MR-i: high-speed dual-cameras hyperspectral imaging FTS

From scientific research to deployable operational solutions, Fourier-Transform Infrared (FT-IR) spectroradiometry is widely used for the development and enhancement of military and research applications. These techniques include targets IR signature characterization, development of advanced camouflage techniques, aircraft engines plumes monitoring, meteorological sounding and atmospheric composition analysis such as detection and identification of chemical threats. Imaging FT-IR spectrometers have the capability of generating 3D images composed of multiple spectra associated with every pixel of the mapped scene. That data allow for accurate spatial characterization of targets signature by resolving spatially the spectral characteristics of the observed scenes. MR-i is the most recent addition to the MR product line series and generates spectral data cubes in the MWIR and LWIR. The instrument is designed to acquire the spectral signature of various scenes with high temporal, spatial and spectral resolution. The four port architecture of the interferometer brings modularity and upgradeability since the two output ports of the instrument can be populated with different combinations of detectors (imaging or not). For instance to measure over a broad spectral range from 1.3 to 13 μm, one output port can be equipped with a LWIR camera while the other port is equipped with a MWIR camera. Both ports can be equipped with cameras serving the same spectral range but set at different sensitivity levels in order to increase the measurement dynamic range and avoid saturation of bright parts of the scene while simultaneously obtaining good measurement of the faintest parts of the scene. Various telescope options are available for the input port. Overview of the instrument capabilities will be presented as well as test results and results from field trials for a configuration with two MWIR cameras. That specific system is dedicated to the characterization of airborne targets. The expanded dynamic range allowed by the two MWIR cameras enables to simultaneously measure the spectral signature of the cold background and of the warmest elements of the scene (flares, jet engines exhausts, etc.).

IRCM spectral signature measurements instrumentation featuring enhanced radiometric accuracy

Hyperspectral Infrared (IR) signature measurements are performed in military applications including aircraft- and –naval vessel stealth characterization, detection/lock-on ranges, and flares efficiency characterization. Numerous military applications require high precision measurement of infrared signature characterization. For instance, Infrared Countermeasure (IRCM) systems and Infrared Counter-Countermeasure (IRCCM) system are continuously evolving. Infrared flares defeated IR guided seekers, IR flares became defeated by intelligent IR guided seekers and Jammers defeated the intelligent IR guided seekers [7]. A precise knowledge of the target infrared signature phenomenology is crucial for the development and improvement of countermeasure and counter-countermeasure systems and so precise quantification of the infrared energy emitted from the targets requires accurate spectral signature measurements. Errors in infrared characterization measurements can lead to weakness in the safety of the countermeasure system and errors in the determination of detection/lock-on range of an aircraft. The infrared signatures are analyzed, modeled, and simulated to provide a good understanding of the signature phenomenology to improve the IRCM and IRCCM technologies efficiency [7,8,9]. There is a growing need for infrared spectral signature measurement technology in order to further improve and validate infrared-based models and simulations. The addition of imagery to Spectroradiometers is improving the measurement capability of complex targets and scenes because all elements in the scene can now be measured simultaneously. However, the limited dynamic range of the Focal Plane Array (FPA) sensors used in these instruments confines the ranges of measurable radiance intensities. This ultimately affects the radiometric accuracy of these complex signatures. We will describe and demonstrate how the ABB hyperspectral imaging spectroradiometer features enhanced the radiometric accuracy of spectral signature measurements of infrared military targets.

Automated turbulences jitters correction with a dual ports imaging Fourier-transform spectrometer

When the scene observed by an imaging Fourier-Transform Spectrometer is not stable in amplitude or in position during the time it takes to acquire to spectrum, spectro-radiometric artifacts are generated. These artifacts reduce the radiometric accuracy and may also damage the spectral line shape. The displacements of the scene in the field of view can be due to air turbulence, platform jitters or scene jitters. We describe an automated correction process based on the information provided by the second output port of a two-port imaging FTS. Corrected and uncorrected data will be compared.

A New Marine Atmospheric Emitted Radiance Interferometer for Shipboard Atmospheric and Oceanic Observations

The Marine-Atmospheric Emitted Radiance Interferometer (M-AERI) is a robust, accurate seagoing instrument that measures thermal emission spectra from the sea surface and marine atmosphere. Results from the first shipboard deployment of a new M-AERI instrument are presented.

Reduction of artifacts from scene intensity fluctuations in Hyperspectral Images Using Four-Port Imaging Spectroradiomete

Scene intensity fluctuations during acquisition create artifacts in the acquired spectra of imaging Fourier Transform Spectrometers. We describe a correction process based on the information provided by the second output of a four-port imaging FTS.

Infrared signature measurements with the ABB dual-band hyperspectral imager

MR-i is an imaging Fourier-Transform spectro-radiometer. This field instrument generates spectral datacubes in the MWIR and LWIR. It is designed to acquire the spectral signatures of rapidly evolving events. The spectroradiometer is modular. The two output ports of the instrument can be populated with different combinations of detectors (imaging or not). For instance, to measure over a broad spectral range one output port can be equipped with a LWIR camera while the other port is equipped with a MWIR camera. No dichroic filters are used to split the bands, hence enhancing the sensitivity. Both ports can be equipped with cameras imaging the same spectral range but set at different sensitivity levels in order to increase the measurement dynamic range and avoid saturation of bright parts of the scene while simultaneously obtaining good measurements of the faintest parts of the scene. Various telescope options can be used for the input port.

Standoff aircraft IR characterization with ABB dual-band hyper spectral imager

Remote sensing infrared characterization of rapidly evolving events generally involves the combination of a spectro-radiometer and infrared camera(s) as separated instruments. Time synchronization, spatial coregistration, consistent radiometric calibration and managing several systems are important challenges to overcome; they complicate the target infrared characterization data processing and increase the sources of errors affecting the final radiometric accuracy. MR-i is a dual-band Hyperspectal imaging spectro-radiometer, that combines two 256 x 256 pixels infrared cameras and an infrared spectro-radiometer into one single instrument. This field instrument generates spectral datacubes in the MWIR and LWIR. It is designed to acquire the spectral signatures of rapidly evolving events. The design is modular. The spectrometer has two output ports configured with two simultaneously operated cameras to either widen the spectral coverage or to increase the dynamic range of the measured amplitudes. Various telescope options are available for the input port. Recent platform developments and field trial measurements performances will be presented for a system configuration dedicated to the characterization of airborne targets.

MR-i — overview and first results of the ABB high speed hyperspectral imaging spectroradiometer

With more than 35 years of innovation in spectroscopy, ABB presents its most recent addition to the proven MR product line. This instrument, called MR-i, is a fast imaging Fourier Transform spectroradiometer. It generates spectral data cubes in the MWIR and LWIR and is designed to acquire the spectral signature of various scenes with high temporal, spatial and spectral resolution. MR-i features the MR series 4 ports FTIR architecture enhanced for imaging spectroradiometry. Its architecture is modular and can be configured to support several applications and measurement scenarios for improved performances and extended hyperspectral imaging capabilities. An overview of the new MR-i design and capabilities will be presented as well as the current product development status.

An interferometer for compact imaging spectrometer

We present the recent development of a compact Michelson-like interferometer for an imaging Fourier Transform Spectrometer (IFTS). The interferometer has a mass of less than 600 g and dimensions of about 60 mm x 90 mm x 100 mm. It is designed to be stiff to reduce its sensitivity to vibrations. Its maximum optical path difference is 1 cm. Despite its small size it can support an etendue of 9.2x10-7 m2 sr. This interferometer is well suited to serve as the modulator for a small IFTS when mass and volume are restricted such as onboard planetary probes, UAV, etc. This interferometer can be adapted to a wide variety of infrared imaging detectors. It is a building block upon which can be designed a large range of custom infrared imaging spectrometers.