Luc Levesque

Laser drilling and routing in optical fibers and tapered micropipettes using excimer, femtosecond, and CO2 lasers

We used an excimer laser (193 nm), a femtosecond laser (775 nm) and a CO2 laser (10.6 µm) to drill cylindrical holes in fused silica optical fibers and in glass micro-pipettes. CO2 laser-drilling using tip processing results in tapered holes with larger diameters than the holes drilled with the excimer and the femtosecond laser. Although routing of holes of various shapes results in sharper edges and a higher aspect ratio when the femtosecond laser is used, the CO2 laser could still be used to route rectangular holes in fused silica optical fibers. Albeit hole dimensions and details are smaller when micromachined with the excimer and the femtosecond lasers, the optical fibers are very brittle at the end of the process. CO2 lasers offer the advantage of producing higher fused silica ablation rates with much better polished surfaces and a better mechanical integrity, which are usually more suitable in some applications.

A novel multipixel imaging differential standoff chemical detection sensor

ABB Bomem is expanding its line of infrared remote sensing products with the addition of a new multipixel imaging spectroradiometer. This hyperspectral instrument is based on the proven MR spectroradiometers. The instrument is modular and support several configurations. One of its configurations is optimised for differential acquisition in the VLWIR (cut-off near 14 μm) to support research related to the stand-off detection and quantification of chemicals. In that configuration, the instrument is equipped with a dualinput telescope to perform optical background subtraction. The resulting signal is the differential between the spectral radiance entering each input port.

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.).

Design and Qualification of the TANSO Interferometer

The Greenhouse gases Observing SATellite will monitor global distributions of CO2. This paper presents the interferometer designed for the Thermal And Near infrared Sensor for carbon Observation FTS along with qualification and performance verification activities.

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.).

Overview of the iCATSI multi-pixels standoff chemical detection sensor and the MR-i imaging spectroradiometer

ABB Bomem is expanding its line of infrared remote sensing products with the addition of a new imaging spectroradiometer. The instrument is modular and support several configurations. One of its configurations is a multipixels sensor optimised for differential acquisition in the VLWIR to support research related to chemical detection. In that configuration, the instrument is equipped with a dual-input telescope to perform optical background subtraction. The resulting signal is the differential between the spectral radiance entering each input port. The other configuration is a general purpose imaging spectroradiometer designed to acquire the spectral signature of rapid events and fast targets in infrared. Overview of the design and results from tests and first field trials will be presented.

Hyperspectral imaging spectro radiometer improves radiometric accuracy

Reliable and accurate infrared characterization is necessary to measure the specific spectral signatures of aircrafts and associated infrared counter-measures protections (i.e. flares). Infrared characterization is essential to improve counter measures efficiency, improve friend-foe identification and reduce the risk of friendly fire. Typical infrared characterization measurement setups include a variety of panchromatic cameras and spectroradiometers. Each instrument brings essential information; cameras measure the spatial distribution of targets and spectroradiometers provide the spectral distribution of the emitted energy. However, the combination of separate instruments brings out possible radiometric errors and uncertainties that can be reduced with Hyperspectral imagers. These instruments combine both spectral and spatial information into the same data. These instruments measure both the spectral and spatial distribution of the energy at the same time ensuring the temporal and spatial cohesion of collected information. This paper presents a quantitative analysis of the main contributors of radiometric uncertainties and shows how a hyperspectral imager can reduce these uncertainties.

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.