{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T00:04:28Z","timestamp":1772841868847,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2011,11,23]],"date-time":"2011-11-23T00:00:00Z","timestamp":1322006400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this article we describe a new instrumental setup at the University of Twente Faculty ITC with an optimized processing chain to measure absolute directional-hemispherical reflectance values of typical earth science samples in the 2.5 to 16 \u00b5m range. A Bruker Vertex 70 FTIR spectrometer was chosen as the base instrument. It was modified with an external integrating sphere with a 30 mm sampling port to allow measuring large, inhomogeneous samples and quantitatively compare the laboratory results to airborne and spaceborne remote sensing data. During the processing to directional-hemispherical reflectance values, a background radiation subtraction is performed, removing the effect of radiance not reflected from the sample itself on the detector. This provides more accurate reflectance values for low-reflecting samples. Repeat measurements taken over a 20 month period on a quartz sand standard show that the repeatability of the system is very high, with a standard deviation ranging between 0.001 and 0.006 reflectance units depending on wavelength. This high level of repeatability is achieved even after replacing optical components, re-aligning mirrors and placement of sample port reducers. Absolute reflectance values of measurements taken by the instrument here presented compare very favorably to measurements of other leading laboratories taken on identical sample standards.<\/jats:p>","DOI":"10.3390\/s111110981","type":"journal-article","created":{"date-parts":[[2011,11,23]],"date-time":"2011-11-23T11:12:28Z","timestamp":1322046748000},"page":"10981-10999","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":46,"title":["Thermal Infrared Spectrometer for Earth Science Remote Sensing Applications\u2014Instrument Modifications and Measurement Procedures"],"prefix":"10.3390","volume":"11","author":[{"given":"Christoph","family":"Hecker","sequence":"first","affiliation":[{"name":"Department of Earth Systems Analysis, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Hengelosestraat 99, P.O. Box 37, Enschede 7500AA, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Simon","family":"Hook","sequence":"additional","affiliation":[{"name":"Earth Surface Science, Science Division, Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mark van der","family":"Meijde","sequence":"additional","affiliation":[{"name":"Department of Earth Systems Analysis, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Hengelosestraat 99, P.O. Box 37, Enschede 7500AA, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wim","family":"Bakker","sequence":"additional","affiliation":[{"name":"Department of Earth Systems Analysis, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Hengelosestraat 99, P.O. Box 37, Enschede 7500AA, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Harald van der","family":"Werff","sequence":"additional","affiliation":[{"name":"Department of Earth Systems Analysis, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Hengelosestraat 99, P.O. Box 37, Enschede 7500AA, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Henk","family":"Wilbrink","sequence":"additional","affiliation":[{"name":"GeoScience Laboratory, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Hengelosestraat 99, P.O. Box 37, Enschede 7500AA, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Frank van","family":"Ruitenbeek","sequence":"additional","affiliation":[{"name":"Department of Earth Systems Analysis, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Hengelosestraat 99, P.O. Box 37, Enschede 7500AA, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Boudewijn de","family":"Smeth","sequence":"additional","affiliation":[{"name":"Department of Earth Systems Analysis, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Hengelosestraat 99, P.O. Box 37, Enschede 7500AA, The Netherlands"},{"name":"GeoScience Laboratory, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Hengelosestraat 99, P.O. Box 37, Enschede 7500AA, The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Freek van der","family":"Meer","sequence":"additional","affiliation":[{"name":"Department of Earth Systems Analysis, Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Hengelosestraat 99, P.O. 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Solid Earth"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"24195","DOI":"10.1029\/1999JE001034","article-title":"Quantitative compositional analysis using thermal emission spectroscopy: Application to igneous and metamorphic rocks","volume":"104","author":"Feely","year":"1999","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/0034-4257(93)90077-B","article-title":"The midinfrared reflectance of mineral mixtures (7\u201314 \u03bcm)","volume":"45","author":"Thomson","year":"1993","journal-title":"Rem. Sens. Environ"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Bedell, R., Crosta, A.P., and Grunsky, E. (2009). Remote Sensing and Spectral Geology, Society of Economic Geologists.","DOI":"10.5382\/Rev.16"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Milam, K.A., McSween, H.Y., and Christensen, P.R. (2007). Plagioclase compositions derived from thermal emission spectra of compositionally complex mixtures: Implications for Martian feldspar mineralogy. J. Geophys. Res. Planets, 112.","DOI":"10.1029\/2006JE002880"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"849","DOI":"10.2138\/am-1997-9-1002","article-title":"Exsolution and Al-Si disorder in alkali feldspars: Their analysis by infrared spectroscopy","volume":"82","author":"Zhang","year":"1997","journal-title":"Am. Mineral"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"9717","DOI":"10.1029\/1999JE001113","article-title":"Determining the modal mineralogy of mafic and ultramafic igneous rocks using thermal emission spectroscopy","volume":"105","author":"Hamilton","year":"2000","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"4188","DOI":"10.3390\/s110404188","article-title":"Can infrared spectroscopy be used to measure change in potassium nitrate concentration as a proxy for soil particle movement?","volume":"11","author":"Luleva","year":"2011","journal-title":"Sensors"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"E03007:1","DOI":"10.1029\/2003JE002197","article-title":"Thermal infrared analysis of weathered granitic rock compositions in the Sacaton Mountains, Arizona: Implications for petrologic classifications from thermal infrared remote-sensing data","volume":"109","author":"Michalski","year":"2004","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"E04001:1","DOI":"10.1029\/2003JE002097","article-title":"Accuracy of plagioclase compositions from laboratory and Mars spacecraft thermal emission spectra","volume":"109","author":"Milam","year":"2004","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1016\/j.jag.2011.08.009","article-title":"Hyperspectral remote sensing of evaporate minerals and associated sediments in Lake Magadi area, Kenya","volume":"14","author":"Kodikara","year":"2012","journal-title":"Int. J. Appl. Earth Observ.Geoinform"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3733","DOI":"10.3390\/s8063733","article-title":"A spatial-spectral approach for visualization of vegetation stress resulting from pipeline leakage","volume":"8","author":"Jansma","year":"2008","journal-title":"Sensors"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1016\/j.rse.2005.04.030","article-title":"Surface mineral mapping at Steamboat Springs, Nevada, USA, with multi-wavelength thermal infrared images","volume":"99","author":"Vaughan","year":"2005","journal-title":"Rem. Sens. Environ"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Griffiths, P.R., and De Haseth, J.A. (2007). Fourier Transform Infrared Spectrometry, Wiley & Sons. [2nd ed].","DOI":"10.1002\/047010631X"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1016\/j.earscirev.2010.07.005","article-title":"Thermal infrared spectroscopy on feldspars\u2014Successes, limitations and their implications for remote sensing","volume":"103","author":"Hecker","year":"2010","journal-title":"Earth Sci. Rev"},{"key":"ref_17","unstructured":"Salisbury, J.W., Walter, L.S., Vergo, N., and D\u2019Aria, D.M. (1991). Infrared (2.1\u201325 \u03bcm) Spectra of Minerals, The Johns Hopkins University Press."},{"key":"ref_18","unstructured":"Koehl, M. (2006). Optosol, Freiburg im Breisgau, Germany, Personal communication,."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"767","DOI":"10.1364\/AO.4.000767","article-title":"Directional reflectance and emissivity of an opaque surface","volume":"4","author":"Nicodemus","year":"1965","journal-title":"Appl. Optic"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"711","DOI":"10.1016\/j.rse.2008.11.007","article-title":"The ASTER spectral library version 2.0","volume":"113","author":"Baldridge","year":"2009","journal-title":"Rem. Sens. Environ"},{"key":"ref_21","unstructured":"Ribeiro da Luz, B. (2011). USGS, Reston, VA, USA. Personal communication,."},{"key":"ref_22","unstructured":"Abbott, E. (2011). JPL, Pasadena, CA, USA. Personal communication,."},{"key":"ref_23","unstructured":"Hanssen, L.M., and Snail, K.A. (2006). Integrating Spheres for Mid- and Near-Infrared Reflection Spectroscopy, John Wiley & Sons, Ltd."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"460","DOI":"10.1364\/JOSA.45.000460","article-title":"Theory of the integrating sphere","volume":"45","author":"Jacquez","year":"1955","journal-title":"J. Opt. Soc. Am"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1364\/AO.29.000129","article-title":"Absolute reflectometer for the mid infrared region","volume":"29","author":"Sheffer","year":"1990","journal-title":"Appl. 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