Multipurpose Spectral Imager

The University Courses on Svalbard, 9170 Longyearbyen, Norway.
Applied Optics (Impact Factor: 1.78). 07/2000; 39(18):3143-53. DOI: 10.1364/AO.39.003143
Source: PubMed


A small spectral imaging system is presented that images static or moving objects simultaneously as a function of wavelength. The main physical principle is outlined and demonstrated. The instrument is capable of resolving both spectral and spatial information from targets throughout the entire visible region. The spectral domain has a bandpass of 12 A. One can achieve the spatial domain by rotating the system's front mirror with a high-resolution stepper motor. The spatial resolution range from millimeters to several meters depends mainly on the front optics used and whether the target is fixed (static) or movable relative to the instrument. Different applications and examples are explored, including outdoor landscapes, industrial fish-related targets, and ground-level objects observed in the more traditional way from an airborne carrier (remote sensing). Through the examples, we found that the instrument correctly classifies whether a shrimp is peeled and whether it can disclose the spectral and spatial microcharacteristics of targets such as a fish nematode (parasite). In the macroregime, we were able to distinguish a marine vessel from the surrounding sea and sky. A study of the directional spectral albedo from clouds, mountains, snow cover, and vegetation has also been included. With the airborne experiment, the imager successfully classified snow cover, leads, and new and rafted ice, as seen from 10.000 ft (3.048 m).

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    • "Development of hyperspectral imaging as a bio-optical tool 239 (R. Pettersen et al. unpublished), were measured with a custom made HI consisting of a solid-state push-broom HI, 2 cm long, 4 cm wide, 600 g, with power requirement of 12 V, 139 mA (Sigernes et al. 2000; Johnsen et al. 2013b). Frame rate was set to 25 images per second and the camera was equipped with a 12-mm Schneider (f:1.2) front lens with aperture set to 2.8 to enhance depth of field. "
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    ABSTRACT: Reflection spectra obtained from hyperspectral imaging can be used as a bio-optical taxonomic identification tool if the pigment composition and the corresponding optical absorption signatures of an organism are known. In this study we elucidate species-specific absorption and corresponding reflection signatures of marine organisms and discuss optical fingerprints from underwater hyperspectral imaging (UHI) for future automated identification of organisms on the seafloor. When mounted on underwater robots, UHI has the potential to be a time- and cost-efficient identification and mapping method covering large areas over a short time. Hyperspectral imaging in vivo and in situ were used to obtain species-specific reflection signatures (optical fingerprints). High performance liquid chromatography, liquid chromatography-mass spectroscopy and nuclear magnetic resonance were used for pigment identification and to obtain species-specific absorption signatures of four marine benthic species; the spoonworm Bonellia viridis, and the sponges Isodictya palmata, Hymedesmia paupertas and Hymedesima sp. Species-specific optical fingerprints based on a UHI-based reflectance signature were verified successfully in the organisms investigated.
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