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Registration of Heat Capacity Mapping Mission day and night images
Neither iterative registration, using drainage intersection maps for control, nor cross correlation techniques were satisfactory in registering day and night HCMM imagery. A procedure was developed which registers the image pairs by selecting control points and mapping the night thermal image to the daytime thermal and reflectance images using an affine transformation on a 1300 by 1100 pixel image. The resulting image registration is accurate to better than two pixels (RMS) and does not exhibit the significant misregistration that was noted in the temperature-difference and thermal-inertia products supplied by NASA. The affine transformation was determined using simple matrix arithmetic, a step that can be performed rapidly on a minicomputer.
Infrared imaging of comets
Thermal infrared imaging of comets provides fundamental information about the distribution of dust in their comae and tails. The imaging program at NASA Marshall Space Flight Center (MSFC) uses a unique 20-pixel bolometer array that was developed to image comets at 8 to 30 micrometer. These images provide the basis for: (1) characterizing the composition and size distribution of particles, (2) determining the mass-loss rates from cometary nuclei, and (3) describing the dynamics of the interaction between the dust and the solar radiation. Since the array became operational in 1985, researchers have produced a unique series of IR images of comets Giacobini-Zinner (GZ), Halley, and Wilson. That of GZ was the first groundbased thermal image ever made of a comet and was used to construct, with visible observations, an albedo map. Those data and dynamical analyses showed that GZ contained a population of large (approximately 300 micrometer), fluffy dust grains that formed a distinict inner tail. The accumulating body of images of various comets has also provided a basis for fruitfully intercomparing comet properties. Researchers also took advantage of the unique capabilities of the camera to resolve the inner, possible protoplanetary, disk of the star Beta Pictoris, while not a comet research program, that study is a fruitful additional application of the array to solar system astronomy.
Real time quantitative imaging for semiconductor crystal growth, control and characterization
A quantitative real time image processing system has been developed which can be software-reconfigured for semiconductor processing and characterization tasks. In thermal imager mode, 2D temperature distributions of semiconductor melt surfaces (900-1600 C) can be obtained with temperature and spatial resolutions better than 0.5 C and 0.5 mm, respectively, as demonstrated by analysis of melt surface thermal distributions. Temporal and spatial image processing techniques and multitasking computational capabilities convert such thermal imaging into a multimode sensor for crystal growth control. A second configuration of the image processing engine in conjunction with bright and dark field transmission optics is used to nonintrusively determine the microdistribution of free charge carriers and submicron sized crystalline defects in semiconductors. The IR absorption characteristics of wafers are determined with 10-micron spatial resolution and, after calibration, are converted into charge carrier density.
Thermal Infrared Spectral Imager for Airborne Science Applications
An airborne thermal hyperspectral imager is under development which utilizes the compact Dyson optical configuration and quantum well infrared photo detector (QWIP) focal plane array. The Dyson configuration uses a single monolithic prism-like grating design which allows for a high throughput instrument (F/1.6) with minimal ghosting, stray-light and large swath width. The configuration has the potential to be the optimal imaging spectroscopy solution for lighter-than-air (LTA) vehicles and unmanned aerial vehicles (UAV) due to its small form factor and relatively low power requirements. The planned instrument specifications are discussed as well as design trade-offs. Calibration testing results (noise equivalent temperature difference, spectral linearity and spectral bandwidth) and laboratory emissivity plots from samples are shown using an operational testbed unit which has similar specifications as the final airborne system. Field testing of the testbed unit was performed to acquire plots of apparent emissivity for various known standard minerals (such as quartz). A comparison is made using data from the ASTER spectral library.
Types of thermal plumes in coastal waters
A large number of thermal images of the surface temperatures of the thermal plumes associated with the once-through cooling of electric power plants show that four kinds of plume occur sufficiently often to be classified as distinct plume types. Each type has implications for both numerical models and measurement strategies.
Finding the Cold Needle in a Warm Haystack: Infrared Imaging Applied to Locating Cryo-cooled Crystals in Loops
Thermally imaging the cryocooling processes of crystals has been demonstrated showing the progression of a cold wave through a crystal from the face closest to the origin of the coldstream ending at the point furthest away. During these studies large volume crystals were clearly distinguished from the loop holding them. Large volume crystals, used for neutron studies, were chosen deliberately to enhance the imaging. The different infrared transmission and reflectance properties of the crystal in comparison to the cryo-protectant are thought to be the parameter that produces the contrast making the crystal visible. As an application of the technology to locating crystals, more small crystals of lysozyme and a bFGF/dna complex were cryo-protected and imaged in large loops. The crystals were clearly distinguished from the vitrified solution. In the case of the bFGF/dna complex the illumination had to be carefully manipulated to enable the crystal to be seen in the visible spectrum. These preliminary results will be presented along with advantages and disadvantages of the technique and a discussion of how it might be applied.
Commercial Systems Validation Overview
The Commercial Systems Validation Laboratory (CSVL) is composed of the 1) Virtual Product Laboratory (VPL), 2) Commercial Instrument Validation Laboratory (CIVL), and 3) In-Flight Verification & Validation Network (IVVN). All three laboratories are described in this viewgraph presentation, which covers the characterization of CCD cameras, hyperspectral sensors, ground reference equipment, and the Multispectral Thermal Imager (MTI). The presentation also includes sections on thermal modeling, measurements taken from a float, and the Scientific Data Purchase (SDP) Program. The section of the SDP profiles four data providers: 1) EarthSat; 2) Intermap; 3) Positive Systems; 4) Space Imaging.
Characteristics of the GOES I-M imager and sounder
The key features and operational characteristics of the thermal imaging and sounding instruments included into the next-generation GOES spacecraft (GOES I-M) are described. The GOES Imager's censor module has five spectral channels, including an eigth-element visible channel, three IR channels, and a water-vapor channel. The GOES Sounder's detector and filter arrangement makes use of four spectral bands: long-wave, mid-wave, short-wave, and visible. Tables of the Imager and the Sounder sensing performance characteristics are presented together with diagrams of the Imager optic parts and the Imager and the Sounder field and scan patterns.
Infrared surface temperature measurements for the surface tension driven convection experiment
In support of the Surface Tension Driven Convection Experiment (STDCE), a planned space transportation system (STS) flight experiment, a commercially available infrared thermal imaging system is used to quantify the imposed thermal signature along the free surface. The system was tested and calibrated for the STDCE with ground-based equivalents of the STDCE hardware. Before using the system, consideration was given to the radiation characteristics of the target (silicone oil). Absorption coefficients were calculated to understand the surface depth as seen by the imager and the penetration depth of the surface heater (CO2 laser). The performance and operational specifications for the imager and image processing system are described in detail to provide an understanding of the equipment. Measurements made with the system were compared to thermocouple measurements and a calculated surface temperature distribution. This comparison showed that in certain regions the IR imager measurements were within 5 percent of the overall temperature difference across the free surface. In other regions the measurements were within + or - 10 percent of the overall temperature gradient across the free surface. The effective emissivity of silicone oil for these experimental conditions was also determined. Measurement errors and their possible solutions are discussed.
P-ACTIVE Project Report
The Phase change material-based actively-tunable filter (P-ACTIVE, Dr. Hyun Jung Kim, the Principal Investigator / PI) project is a NASA Langley Research Center (LaRC)-led research endeavor that began as a NASA CIF (Center Innovation Fund) project in 2019. The goal of P-ACTIVE is to develop all-solid-state tunable optical filters that can serve as low-Size, Weight, and Power (SWaP) replacements to the ubiquitous filter wheel technology current in use, and serve as a starting point for completely new optical component technologies. By using materials commonly used in electronic memory devices, namely chalcogenide phase-change materials (PCMs), in conjunction with nanostructured surfaces with exotic, tailored optical responses (“metasurfaces”), the P-ACTIVE filters are able to tune their optical transmission/reflection behavior in real-time. Because of this new functionality, P-ACTIVE filters are highlighted for NASA science and space programs such as next generation Lidar, landing system (SLS) thermal monitoring, thermal imaging, imaging spectroscopy, and disaster monitoring (e.g., volcanic eruption observations from SmallSats). This document intends to serve as a compendium of the P-ACTIVE project. We begin by describing the project from background science and assume no prior knowledge of the subject. We then address experimental and theoretical results of P-ACTIVE device performance, as well as recent results obtained from the MISSE-14 mission related to space qualification of P-ACTIVE devices and constituent materials. We conclude with a prospective view of the P-ACTIVE technology, and discuss the potential for these filters and other similar metasurface devices to serve NASA’s mission.
Characteristics of the GOES I-M Imager and Sounder
The design and the parameters of the improved thermal-imaging and sounding instruments (the Imager and the Sounder) that will be part of the instrument complements of the next-generation Geostationary Operational Environmental Satellite (GOES I-M) are discussed. The new design incorporates many features that enhance instrumental reliability over the previous GOES radiometric instruments, such as independently functioning Sounder and Imager, redundancy, and more reliable position sensors and lubrication methods. Tables are presented which list the instrument parameters of the GOES I-M Imager and Sounder and the performance characteristics of the two instruments.
Automation of the Image Analysis for Thermographic Inspection
Several data processing procedures for the pulse thermal inspection require preliminary determination of an unflawed region. Typically, an initial analysis of the thermal images is performed by an operator to determine the locations of unflawed and the defective areas. In the present work an algorithm is developed for automatically determining a reference point corresponding to an unflawed region. Results are obtained for defects which are arbitrarily located in the inspection region. A comparison is presented of the distributions of derived values with right and wrong localization of the reference point. Different algorithms of automatic determination of the reference point are compared.
Ground truth spectrometry and imagery of eruption clouds to maximize utility of satellite imagery
Field experiments with thermal imaging infrared radiometers were performed and a laboratory system was designed for controlled study of simulated ash clouds. Using AVHRR (Advanced Very High Resolution Radiometer) thermal infrared bands 4 and 5, a radiative transfer method was developed to retrieve particle sizes, optical depth and particle mass involcanic clouds. A model was developed for measuring the same parameters using TIMS (Thermal Infrared Multispectral Scanner), MODIS (Moderate Resolution Imaging Spectrometer), and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer). Related publications are attached.
Estimation of surface temperature variations due to changes in sky and solar flux with elevation
The magnitude of elevation effects due to changes in solar and sky fluxes, on interpretation of single thermal images and composite products such as temperature difference and thermal inertia, are examined. Simple expressions are derived for the diurnal behavior of the two parameters, by fitting field observations in one tropic (Hawaii) and two semi-arid climates (Wyoming and Colorado) (Hummer-Miller, 1981). It is shown that flux variations with elevation can cause changes in the mean diurnal temperature gradient from -4 to -14 degrees C/km, evaluated at 2000 m. Changes in the temperature-difference gradient of 1 to 2 degrees C/km are also produced which is equivalent to an effective thermal-inertia gradient of 100 W s(exp 1/2)/sq m-K-km. An example is presented showing an elevation effect of 12 degrees C on the day and night thermal scenes of a test site in Arizona.
Evolution of miniature detectors and focal plane arrays for infrared sensors
Sensors that are sensitive in the infrared spectral region have been under continuous development since the WW2 era. A quest for the military advantage of 'seeing in the dark' has pushed thermal imaging technology toward high spatial and temporal resolution for night vision equipment, fire control, search track, and seeker 'homing' guidance sensing devices. Similarly, scientific applications have pushed spectral resolution for chemical analysis, remote sensing of earth resources, and astronomical exploration applications. As a result of these developments, focal plane arrays (FPA) are now available with sufficient sensitivity for both high spatial and narrow bandwidth spectral resolution imaging over large fields of view. Such devices combined with emerging opto-electronic developments in integrated FPA data processing techniques can yield miniature sensors capable of imaging reflected sunlight in the near IR and emitted thermal energy in the Mid-wave (MWIR) and longwave (LWIR) IR spectral regions. Robotic space sensors equipped with advanced versions of these FPA's will provide high resolution 'pictures' of their surroundings, perform remote analysis of solid, liquid, and gas matter, or selectively look for 'signatures' of specific objects. Evolutionary trends and projections of future low power micro detector FPA developments for day/night operation or use in adverse viewing conditions are presented in the following test.
Chromatic Image Analysis For Quantitative Thermal Mapping
Chromatic image analysis system (CIAS) developed for use in noncontact measurements of temperatures on aerothermodynamic models in hypersonic wind tunnels. Based on concept of temperature coupled to shift in color spectrum for optical measurement. Video camera images fluorescence emitted by phosphor-coated model at two wavelengths. Temperature map of model then computed from relative brightnesses in video images of model at those wavelengths. Eliminates need for intrusive, time-consuming, contact temperature measurements by gauges, making it possible to map temperatures on complex surfaces in timely manner and at reduced cost.
Optical data storage and metallization of polymers
The utilization of polymers as media for optical data storage offers many potential benefits and consequently has been widely explored. New developments in thermal imaging are described, wherein high resolution lithography is accomplished without thermal smearing. The emphasis was on the use of poly(ethylene terephthalate) film, which simultaneously serves as both the substrate and the data storage medium. Both physical and chemical changes can be induced by the application of heat and, thereby, serve as a mechanism for high resolution optical data storage in polymers. The extension of the technique to obtain high resolution selective metallization of poly(ethylene terephthalate) is also described.