An overview of the physical principals of imaging spectrometry for detailed characterization of remote objects and of gas vapors is given. The terms multi-spectral, hyperspectral, and ultra-spectral are defined within the framework of applications and instrument system design approaches. History of the development of imaging spectrometers is reviewed. We are at the threshold of major commercial efforts for these instrument systems.

The hyperspectral data and information collection experiment obtained data over the Cuprite Mining District to determine the ability of the system to identify sub-pixel targets. Positive results were obtained for targets of crushed dolomite placed at the base of Kaolinite Hill on top of visibly similar soil. Equally positive results were obtained for Mylar targets placed on Stonewall Playa, with a 5 percent target being detected. However when a dolomite target on the playa was being sought, the Mylar target was also detected. The reasons for this spurious detection are discussed.

There is a widespread perception that hyperspectral imagery may be useful for military broad area tactical surveillance applications in the not-too-distant future, and the government is planning to demonstrate this technology from space within the next three years. In order to support sensor design for such a demonstration, we have developed an algorithm performance simulation that applies linear unmixing techniques to the problem of quasi-real-time ground clutter suppression in hyperspectral images. Our object is to enable top level sensor design tradeoffs to be evaluated and to derive first order estimates of sensor requirements that could potentially enable fully automated timely detection of time-critical tactical military targets over broad areas against a wide variety of terrain types. We describe a simple algorithm for target detection that is single-pass, completely automated, and requires little or no training to detect targets. Monte Carlo simulations on AVIRIS images have been used to measure the performance of this algorithm under realistic conditions and to derive probability of detection and probability of false alarm versus signal to noise ratio in a pair of test images. Although the parameter space is quite large and the exploratory work is still in progress, early results give valuable insight into design requirements for spaceborne hyperspectral sensors to support broad area tactical surveillance applications.

Hyperspectral imaging provides an efficient means of mapping surface mineralogy, however, mineralogic maps produced from these data do not rake into consideration other geologic characteristics such as surface morphology and texture. Similarly, while advanced SAR systems such as the multifrequency, multipolarization SIR-C/X-SAR are well suited to mapping surface morphology parameters, they do not provide any mineralogic information. A combined approach provides visible/infrared imaging spectrometer (AVIRIS) and shuttle imaging radar-C (SIR-C/X-SAR) data for geologic mapping. AVIRIS data were calibrated to reflectance, spectral endmembers were selected, and abundance images were generated for specific endmembers using spectral mixing and matched filtering. SIR-C images were synthesized from the complex scattering matrix data for selected frequency/polarization combinations and X-SAR data were co- registered to form a multifrequency, multipolarization data set. The SAR and AVIRIS data were map-referenced and analyzed together along with Landsat TM and thermal infrared multispectral scanner data using geometric visualization and analysis techniques developed for hyperspectral data analysis. The results provide an example of the viability of an extended spectral signature approach, segmenting the terrain i top distinct lithologic units on the basis of combined mineralogic and morphologic characteristics. This approach has significant implications for future remote sensing missions and sensors. The research also demonstrates that multispectral and hyperspectral techniques can be successfully applied to combined optical/SAR data sets.

The SWIR full spectrum imager (SFSI) is a hyperspectral push-broom imager, acquiring imagery in 120 0.010 micrometers wide bands simultaneously covering the 1.20 micrometers to 2.47 micrometers spectral region. During the first flights of the instrument hyperspectral imagery was acquired over a calcite quarry and a dolomite quarry. Both these minerals show distinctive carbonate absorption features in the 1.7 to 2.5 micrometers region. These absorption features are centered at wavelengths approximately 0.1 micrometers shorter in dolomite than in calcite. The two minerals are clearly distinguished using a single Gaussian fit to the prominent carbonate absorption feature near approximately 2.3 micrometers in the quarry reflectance data from the SFSI test flights. The spectral resolution of the airborne spectra also allowed the 2.3 micrometers absorption feature to be resolved into tow closely spaced features. Both these absorption features show the mineralogical shift in band center. This has also been seen in laboratory spectra and a detailed comparison with this data is made.

Spectral imaging data have been acquired with the Navy HYDICE (the hyperspectral digital imagery collection experiment) instrument from an aircraft. Similar data will soon be collected with the NASA HSI instrument from the Lewis spacecraft. The majority of users of imaging spectrometer data are interested in studying surface properties. Therefore, atmospheric absorption and scattering effects must be removed from imaging spectrometer data, so that surface reflectance spectra can be derived. Previously, an operational atmosphere removal algorithm, which used the 5S code for modeling the atmospheric scattering effects and the Malkmus narrow band model for modeling atmospheric gaseous transmittances, was specifically designed for deriving surface reflectances from spectral imaging data collected by the NASA JPL airborne visible/infrared imaging spectrometer (AVIRIS). We have recently updated this algorithm by replacing the 5S code, which requires that the sensor be at the top of the atmosphere, with the 6S code, which accommodates sensors at any altitudes. The updated algorithm allows processing of imaging spectrometer data acquired from low- and high-altitude aircraft platforms, and from satellite platforms. We are currently developing another algorithm that uses a line-by line code to calculate atmospheric gaseous transmittances for processing imaging spectrometer data with spectral resolution between approximately 0.5 and 10 nm.

Coordinated flights of two calibrated airborne imaging spectrometers, HYDICE and AVIRIS, were conducted on June 22, 1995 over Lake Tahoe. As part of HYDICE's first operational mission, one objective was to test the system performance over the dark homogeneous target provided by the clear deep waters of the lake. The high altitude and clear atmosphere makes Lake Tahoe a simpler test target than near-shore marine environments, where large aerosols complicate atmospheric correction and sediment runoff and high chlorophyll levels make interpretation of he data difficult. Calibrated data from both runoff and high chlorophyll levels make interpretation of the data difficult. Calibrated data from both sensors was provided in physical units of radiance. The atmospheric radiative transfer code, MODTRAN was used to remove the path radiance between the ground and sensor and the skylight reflected from the water surface. The resulting water-leaving spectrometer, and with values calculated form in-water properties using the HYDROLIGHT radiative transfer code. The agreement of the water-leaving radiance for the HYDICE data, the ground-truth spectral measurements, and the results of the radiative transfer code are excellent for wavelengths greater than 0.45 micrometers . The AVIRIS flight took place more than an hour closer to noon, which makes the radiance measurements not directly comparable. Comparisons to radiative transfer output for this later time indicate that the AVIRIS data is strongly by sun glint. Because water-leaving radiance is dependent upon the characteristics of the water, it can be analyzed for some of those properties. Using the CZCS algorithm based on the water-leaving radiance at two wavelengths, the chlorophyll content of Lake Tahoe was computed from the HYDICE and ground-truth data. Resulting values are slightly higher than measurements made two weeks earlier from water samples, indicating a growth in the phytoplankton population which is very plausible given the intervening atmospheric conditions. The success in determining water-leaving radiance and interpreting it for pigment concentration are very positive results for this early HYDICE flight. The interpretations made so far do not make use of the full spectral content of the data, so much room for advancement remains.

An imaging spectrometer has been developed for the NASA small satellite technology initiative (SSTI) which provides 30 meter resolution earth images in 384 continuous spectral bands from 0.4 micrometers to 2.5 micrometers . The instrument includes a 5 meter resolution Panchromatic camera and a calibration subsystem. The hyperspectral imager (HSI) payload was developed for the Lewis satellite in 24 months and is scheduled to fly later this year. This paper describes the HSI design, development and performance.

Recent studies have demonstrated the potential for exploring spectral discriminates in the thermal infrared for day/night surveillance and targeting of military targets in situations where the thermal contrast is low. Although the spectral discriminates have been found to be very subtle in most cases, good detection performance is achievable due to the generally high band-to-band spectral correlation of the background. This, however, presents a challenging set of requirements for infrared multispectral and hyperspectral sensors designed for this application. In this paper, we examine the merits and limitations of various design approaches, including imaging Michelson interferometers, dispersive spectrometers, and spatial Fourier transform spectrometers. The comparison is based on detailed sensor modeling as well as laboratory and field measurements of state-of-the-art instruments: a dispersive spectrometers and a n imaging Fourier transform spectrometer. The primary emphasis of this paper is the design of a hyperspectral sensor for tower-based and subsequent airborne data collection. Implications for operational multispectral sensor designs are also given.

We describe the design and performance of an infrared imaging spectrograph that was first used as an airborne sensor in October, 1995. This instrument, called the spatially-enhanced broadband array spectrograph system (SEBASS), is intended to explore the utility of hyperspectral infrared sensors for remotely identifying solids, liquids, gases, and chemical vapors in the 2 to 14 micrometers 'chemical fingerprint' spectral region. The instrument, which is an extension of an existing non-imaging spectrograph uses two spherical-faced prisms to operate simultaneously in the atmospheric transmission windows found between 2.0 and 5.2 micrometers and between 7.8 and 13.4 micrometers (LWIR). ALthough the SEBASS instrument is designed primarily for use from an aircraft platform, it was used in March 1996 for a tower-based collection.

Reflectance characteristics of typical Earth surface materials are strongly dependent on the incident illumination angle of the sun and viewing geometry of the sensor to the scene. This relationship is summarized in the bidirectional reflectance distribution function (BRDF) of the surface material under investigation. The BRDF, defined to be the ratio of reflected radiance to the incident radiant flux density striking a surface, cannot be measured directly in an operational setting. Laboratory measurements of surface BRDF are possible but tend to be tedious and time consuming. Consequently, the BRDF is often specified with models applied to laboratory spectra obtained under ideal and controlled conditions. In this paper, we evaluate the utility of BRDF modeling in statistical classification/discrimination of Earth surface materials by considering the bidirectional reflectance for multiple viewing angle configurations and the resulting separability between classes.

Ground-based observations of the terrestrial dayglow emissions require the measurement of a small signal embedded in a large background. A high sensitivity imaging spectrometer has been developed to perform these measurements. The instrument is capable of operating over a full diurnal cycle with photometric like sensitivity to provide simultaneous measurements from the ground of the rich spectral content of the daytime mesosphere, thermosphere and ionosphere spectra. This low-f-number wide field-of-view imaging spectrometer is capable of measuring the day-glow spectrum over the wavelength range of 300 to 880 nm with a very high spectral resolution of 0.5 nm. The spectrometer has a field-of-view of 14 degrees without any vignetting. The spectrometer is designed to work with a 1024 by 1024 pixel UN-enhanced CCD detector having a 24.6 mm by 24.6 mm imaging area. A five-element telecentric lens group has been designed to achieve a compact and low cost package. The symmetric configuration of this lens group eliminates the optical distortions to permit the use of a simple curved slit. Three identical lens groups have been used for the telescope, collimator, and imaging optics to simplify the design and to reduce the fabrication cost. The optical design and performance analysis results for this imaging spectrometer are presented. The optomechanical design and modeling of the instrument is also discussed.

The tremendous potential for hyperspectral imagery as a remote sensing tool has driven the development of TRW's TRWIS III hyperspectral imager. This instrument provides 384 contiguous spectral channels at 5 nm to 6.25 nm spectral resolution covering the 400 nm to 2450 nm wavelength range. The spectra of each pixel in the scene are gathered simultaneously at signal to noise ratios of several hundred to one for typical Earth scenes. Designed to fly on a wide range of aircraft and with variable frame rate, eh ground resolution can be varied from approximately 30 cm to 11 m depending on the aircraft altitude. Meeting critical performance requirements for image quality, co-registration of spectral samples, spectral calibration, noise, and radiometric accuracy are important to the success of the instrument. TRWIS III performance has been validated and the instrument has been radiometrically calibrated using TRW's multispectral test bed. This paper discusses the characterization and calibration process, results of the measurements, and instrument artifacts of potential interest to data users.

MERIS is a passive optical instrument, that will fly on the first polar orbiting earth observation mission ENVISAT. The development of this instrument is currently carried by an international team led by AEROSPATIALE. The instrument primary mission goal is to monitor bio-optical ocean parameters on a large scale. Secondary goals of MERIS include atmospheric investigation on cloud and aerosols parameters and on land surface processes. The instrument will acquire 15 spectral images, programmable in width and position with a spectral sampling interval of 1.25 nm within the spectral range of 390nm to 1040nm. MERIS images will have a swath width of 1100km and spatial resolution of 300m.

The Phillips Laboratory Advanced Electro-Optical System (AEOS) comprises an observatory facility, a united computer network, a 3.63 meter telescope, and an associated sensor suite that will become operational beginning in 1997. Space object identification is the primary mission for AEOS; however, astronomical applications and other visiting experiments are readily supported by the system design. The AEOS sensor suite functions derive from Air Force Space Command requirements, and incorporate high resolution imagery and multi-band radiometry performed over a broad range of wavelengths. Data collection capabilities are optimized for the rapid temporal variations in observed target brightness that arise from both intrinsic target variability and changing atmospheric characteristics during the course of an observation.

This paper describes a method for cloud cover assessment using computer-based analysis of multi-band Landsat images. The objective is to accurately determine the percentage of cloud cover in an efficient manner. The 'correct' value is determined by an expert's visual assessment. Acceptable error rates are +/- 10 percent from the visually determined coverage. This research improves upon an existing algorithm developed for use by the EROS data center several years ago. The existing algorithm uses threshold values in bands, 3, 5 and 6 based on the expected frequency response for clouds in each band. While this algorithm is reasonably fast, the accuracy is often unsatisfactory. The dataset used in developing the new method contained 329 subsampled, 7-band Landsat browse images with wide geographic coverage and a variety of cloud types. This dataset, provided by the EROS Data Center, also specifies the visual cloud cover assessment and the cloud cover assessment using the current automated algorithm. Mask images, separating cloud and non- cloud pixels, were developed for a subset of these images. The new approach is statistically based, developed forma multi-dimensional histogram analysis of a training subset. Images from a disjoint test set wee then classified. Initial results are significantly more accurate than the existing automated algorithm.

Infrared spectral sensors are being investigated as a means for day and night target detection. Target detection performance was estimated using the multiband signal-to- clutter (SCR). The average SCR for a variety of targets and back-grounds can be calculated from Fourier transform spectrometer measurements previously made at vegetated and desert locations. The variation in average SCR was examined as a function of number of spectral bands, locations of bands, and potential sensor noise level for a variety of air-to-ground target detection geometries. The results are useful for assessing the utility and feasibility of infrared spectral target detection and also for specifying future sensor parameters.

Technological improvements in optical sensors have resulted in the collection of spectral information across hundreds of very narrow bands thereby giving analysts detailed spectral signatures not available a few years ago. While useful for identifying materials in a laboratory, the detailed spectral signatures of current hyperspectral sensors present much more information than required for discrimination between materials on the Earth's surface. The sheer volume of spectral information can be overwhelming and has lead to research efforts aimed at selecting only those features useful for the task at hand. In this paper, a method based on maximizing the Bhattacharyya distance to select an optimal subset of spectral bands is presented and applied in discriminating between several mineral classes from the USGS Spectral Library database.

A diffractive optic image spectrometer has been designed and prototyped. Three dimensional spectral/spatial DOE imaging theory has been developed to simulate DOIS performance. The system's point spread function has been theoretically modeled and experimentally determined. The prototype has been characterized and demonstrated with a variety of targets. Three deconvolution algorithms have been implemented with the experimental 3D OTF and applied to recorded target images. The results shown demonstrate the high resolving power available with this approach.

We have constructed a portable computed tomography imaging spectrometer (CTIS) based on a previous laboratory-bench version. This spectrometer features a computer-generated phase-only hologram as the dispersive element and collects spatial and spectral data from the diffracted orders. CTIS is capable of flash spectral imaging. Reconstruction of the image cube from raw data is achieved by computed-tomography techniques. Other improvements from the original design include a more modular design, an automated and more precise calibration technique, and the inclusion of constraints in the image cube reconstruction. Reconstruction results compare favorably with measurements by a fiber spectrometer. Keywords: Imaging spectrometry, computed tomography, flash spectral imaging.

We present a new algorithm for image restoration with application to image spectrometry, combining two radically different techniques: the singular value decomposition (SVD) and the method of projections onto convex sets (POCS). The SVD technique is used to obtain an initial estimate of the unknown image and to establish correspondence between the missing data and the spectral description of the image. The iterative method of convex projections is then applied to the estimate, regaining the missing data by enforcing a sequence of constraints on the reconstructed object. We report results of investigations of the SVD-POCS method and demonstrate that the new algorithm leads to significant improvements in the recovered image.

3D is a new type of a highly sensitive near-infrared integral field spectrometer developed at MPE. It has been designed to multiplex spectral as well as spatial information thus obtaining a full data cube in a single integration. At a spectral resolution between 1000 and 2000 and a field of view of 16 by 16 pixels, optimized for subarcsecond spatial resolution imaging spectroscopy, it has a much higher efficiency compared to conventional astronomical techniques. Combining the advantages of imaging and spectroscopy increases the observing efficiency on small objects by such a large factor over existing grating or Fabry-Perot spectrometers that subarcsecond near-IR spectroscopy on faint Seyferts, starbursts, quasars or distant galaxies clusters becomes feasible for the first time on 4m class telescopes. Outfitting one of the upcoming 8-10 m class telescopes with a 3D type instrument will provide a powerful tool for diffraction-limited integral field spectroscopic research in particular on faint highly redshifted galaxies in the early universe. The basic design of 3D as well as recent results and future plans are presented.

This paper describes the development of a multispectral imaging (MSI) device using AN acousto-optic tunable filter (AOTF). A 2D charge-coupled device (CCD) was used as a detector. The AOTF was used as a wavelength selector. Unlike a tunable grating or prism based monochromator, the tunable filter has no moving parts, and it can be rapidly tuned to any wavelength in its operating range. The large aperture of the AOTF and its high spatial resolution allowed the optical image from an IFP to be recorded by the CCD. These characteristics, combined with their small size, make AOTFs important new alternatives to conventional monochromators, especially for spectral imaging in biomedical applications.

Nonlinear excitation of fluorophores through molecular absorption of two or three near infrared photons from the tightly focused femtosecond pulses of a mode-locked laser offers the cellular biologist an unprecedented panoply of biomolecular indicators for microscopic imaging and cellular analysis. Measurements of the two-photon excitation spectra of more than twenty ultra-violet and visible absorbing fluorophores from 690 to 1050 nm reveal useful cross sections for near infrared excitation, providing an artist's palette of emission markers and chemical indicators for living biological preparations. Measurements of three-photon fluorophore excitation spectra now define alternative windows of relatively benign wavelength to excite deeper UV fluorophores. The three-photon excitation spectrum of the amino acid tryptophan, measured 700-900 nm, delivers native fluorescence for imaging and assay of proteins and neurotransmitter sin living tissues. The inherent optical sectioning capabilities of focused nonlinear excitation provides 3D resolution for imaging and avoids out of focus background. Here, we describe the characteristics of the measured nonlinear excitation spectra and define the resulting features of nonlinear microscopy for biological imaging.

During the past year, Kestrel Corporation has designed and built a low cost Fourier transform hyperspectral imager for deployment in a light aircraft. The instrument is a pushbroom imaging spectrometer employing a Sagnac interferometer. The instrument operates over a range of 350- 1050 nm with 256 spectral channels, and a 13 degree FOV with an 0.8 mrad IFOV. Installed with the optical instrument are attitude sensors, a scene camera, a downwelling sensor and in-flight calibration equipment. This paper will focus on the description of both the optical system and the support equipment used in this revolutionary instrument.

The throughput advantage associated with Fourier-transform spectrometers is examined in the context of imaging spectrometers. The imaging throughput advantage is found to be inversely proportional to the number of spatial- resolution elements in the image cube. That number is also known as the space-bandwidth product and indicates an imager's information-collection capability. In the limit of one spatial resolution element, the advantage expression derived here reduces to the formulation presented elsewhere in the literature. A simple expression for the imaging- throughput advantage is also derived for the case of diffraction-limited imaging.

A new hyperspectral imager has recently been developed by Kestrel Corporation for use in light aircraft platforms. The instrument provides 256 spectral channels with 87 cm^-1 spectral bandwidth over the 450 nm to 1000 nm portion of the spectrum. Operated as a pushbroom imager, the FTVHSI has been shown to have a IFOV of 0.75 mrad, and a FOV of 0.23 rad. The sensor includes an internal spectral/radiometric calibration source, a self contained spectrally resolved downwelling sensor, and complete line of sight and GPS positioning information. The instrument is now operating from a Cessna TU-206 single engine aircraft.

Current hyperspectral imaging cameras are typically limited in throughput either by a slit or other optical geometries requiring small solid angle instantaneous fields of view. The high etendue imaging Fourier transform spectrometer optical design is a new optical geometry for the production of spectral autocorrelation fringe modulation over an image plane defined by a large CCD array. A throughput advantage approaching several hundred appears realizable, with an accompanying increase in signal to noise proportional to 'root N'. THe simple optical implementation of this design will be discussed along with initial experimental results.

In this paper, two compression schemes are presented to meet the urgent needs of compressing the huge volume and high data rate of imaging spectrometer images. According to the multidimensional feature of the images and the high fidelity requirement of the reconstruction, both schemes were devised to exploit the high redundancy in both spatial and spectral dimension based on the mature wavelet transform technology. Wavelet transform was applied here in two ways: First, with the spatial wavelet transform and the spectral DPCM decorrelation, a ratio up to 84.3 with PSNR > 48db's near-lossless result was attained. This is based ont he fact that the edge structure among all the spectral bands are similar while WT has higher resolution in high frequency components. Secondly, with the wavelet's high efficiency in processing the 'wideband transient' signals, it was used to transform the raw nonstationary signals in the spectral dimension. A good result was also attained.

Imaging spectrometer, such as MAIS produces a tremendous volume of image data with up to 5.12 Mbps raw data rate, which needs urgently a real-time, efficient and reversible compression implementation. Between the lossy scheme with high compression ratio and the lossless scheme with high fidelity, we must make our choice based on the particular information content analysis of each imaging spectrometer's image data. In this paper, we present a careful analysis of information-preserving compression of imaging spectrometer MAIS with an entropy and autocorrelation study on the hyperspectral images. First, the statistical information in an actual MAIS image, captured in Marble Bar Australia, is measured with its entropy, conditional entropy, mutual information and autocorrelation coefficients on both spatial dimensions and spectral dimension. With these careful analyses, it is shown that there is high redundancy existing in the spatial dimensions, but the correlation in spectral dimension of the raw images is smaller than expected. The main reason of the nonstationarity on spectral dimension is attributed to the instruments's discrepancy on detector's response and channel's amplification in different spectral bands. To restore its natural correlation, we preprocess the signal in advance. There are two methods to accomplish this requirement: onboard radiation calibration and normalization. A better result can be achieved by the former one. After preprocessing, the spectral correlation increases so high that it contributes much redundancy in addition to spatial correlation. At last, an on-board hardware implementation for the lossless compression is presented with an ideal result.

To counter the best season for exploration of metal mineral under forests using imaging spectrometer, the authors made ground tests at the Zhaoyuan gold mine area of China from the end of April to the middle of November 1991. The characteristic wavelength parameters of the red-edge of the average curves for each time was extracted and analyzed. The results indicate that the three characteristic wavelengths for gold mine area show all annually blue shifts in varying degrees against background area, and the blue shifts in Autumn for the first year leaves, and in Spring for the second-year leaves, especially latter, are the biggest; so Spring and Autumn is the best season for the exploration of metal mineral under Korean Pine Forests.

The visible infrared thermal imaging spectrometer (VIRTIS) is one of the principal payloads to be launched in 2003 on ESA's Rosetta spacecraft. Its primary scientific objective s are to map the surface of the comet Wirtanen, monitor its temperature, and identify the solids and gaseous species on the nucleus and in the coma. VIRTIS will also collet data on two asteroids, one of which has been identified as Mimistrobell. The data is collected remotely using a mapping spectrometer co-boresighted with a high spectral resolution spectrometer. The mapper consists of a Shafer telescope matched to an Offner grating spectrometer capable of gathering high spatial, medium spectral resolution image cubes in the 0.25 to 5 micrometers waveband. The high spectral resolution spectrometer uses an echelle grating and a cross dispersing prism to achieve resolving powers of 1200 to 300 in the 1.9 to 5 micrometers band. Both sub-systems are passively cooled to 130 K and use two Sterling cycle coolers to enable two HgCdTe detector arrays to operate at 70 K. The mapper also uses a silicon back-side illuminated detector array to cover the ultra-violet to near-infrared optical band.

Since March 1996 the Modular Optoelectronic Scanner (MOS) provides remote data from a 820 km sun synchroneous polar orbit. It measures the spectral radiance of the atmosphere- surface system in 18 spectral channels and up to 420 pixels in a 200 km swath. MOS consists of two imaging spectrometers A and B with gratings and a camera C with an interference filter. MOS-AA has 4 channels with a spectral halfwidth (Delta) (lambda) approximately equals 1.4 nm in the absorption band of atmospheric oxygen near 760 nm, MOS-B has 13 channels between 400 and 1010 nm with (Delta) (lambda) approximately equals 10 nm and the MOS-C channel is at 1.6 micrometers with (Delta) (lambda) approximately equals 100 nm. Beside the on ground laboratory calibration as the basis of calculating the spectral radiance of the earth objects, the long time mission requires a periodic recalibration or at least a stability check of instrument properties in orbit to support the reliability of the remote data. Internal lamps and the extraterrestric sun radiation provide actual data sets to derive corrections on remote data if any changes in the performance data arises.

The SWIR full spectrum imager is an imaging spectrometer covering the short-wave infrared from 1220 to 2420 nm, which has been developed for remote sensing from an airborne platform. The sensor has been designed to acquire the full spectrum at high spectral resolution and the full image swath at high spatial resolution simultaneously. The instrument utilizes a 2D detector array, refractive optics and a transmission grating. The fore-optics and spectrograph are f/1.8, and the angular field-of-view is 9.4 degrees. The detector is a 488 line by 512 pixel PtSi Schottky barrier photodiode array. A VME bus computer communicates with the array controller, performs the data acquisition and provides the operator interface. The optical design and sensor system are described: calibration methods and results are presented. Post flight data processing procedures are described and the spectral signal-to-noise ratio is calculated from in-flight data. A sample single-band image from data collected on the JUne 1995 Nevada mission is displayed, spectra of minerals and trees are extracted, and a classification of this image is shown.

This paper discusses a modeling tool that relates the characteristics of a sensor to the mapping products that can be derived from the sensor's imagery. The development of this product-source prediction capability tool will be discussed, as well as its use in DMA MCG applications.