Hyperspectral Imaging
Transcription
Hyperspectral Imaging
Hyperspectral Imaging Updated: 11/10/12 Issue 1 Copyright M.R. Sims 2012 1 Space Research Centre Applications of Hyperspectral Imaging from Planetary Science Through to Healthcare Professor Mark Sims Space Research Centre Department of Physics and Astronomy University of Leicester Hyperspectral Imaging Updated: 11/10/12 Issue 1 Copyright M.R. Sims 2012 2 Space Research Centre Talk Contents Talk Purpose: General Introduction (aimed especially at non-specialists) Overview of Applications + Introduction for more specialist papers to follow Space Research Centre: Applications of Hyperspectral Imaging Talk Contents: Space Research Centre: University of Leicester Hyperspectral vs Multispectral Imaging Hyperspectral Imaging Data Hyperspectral Techniques Hyperspectral Applications Planetary Science Healthcare Concluding Remarks Origins … To the present … 1960 2011 Univ. Leicester Space Research Group established by Royal Society grant of £13,006 Instrumentation development for High Energy Astrophysics, Planetary Exploration, Earth Observation Science, and Knowledge Exchange “to study solar and stellar X-ray emissions” Total grant and contract portfolio ~£20M Space Research Centre The University of Leicester Space Research Centre • ~100 staff and postgraduate students, housed in purpose-built accommodation • Recent expansion: 550 sq.m Michael Atiyah Building Annexe (MAB Phase-3) – occupied November 2010 • Diversified funding for 5 current space projects and for laboratory programme in detectors and optics • Nationally recognised for Knowledge Exchange • Partnerships with National (e.g Astrium) and Regional (e.g Magna Parva) Industry • Interacting with the ESA Centre and Harwell ISIC •Three associated spin-off companies, plus G-STEP, Space IDEAS Hub • Partner in NERC/TSB Centre for Earth Observation Instrumentation Synergy – Connecting the Areas of the Space Research Centre’s Programme Astrophysics Earth Observation Science Science & Technology Research & Development (e.g. sensors) Space Systems Engineering Project Management Knowledge Exchange – ‘Spin-Off ’ Planetary Science Public Outreach Missions and Mission Proposals, October 2011 Mission Instrument Partners JWST BepiColombo EXOMARS Astrosat Gaia Lobster Athena JUICE Plato LOFT Marco-Polo-R SVOM XTIM/XNAV BEXUS MIRI MIXS LMC/XRF/Raman SXT Data Pipeline All-Sky Monitor Various Auroral Imager CCD calibration Large-area detector Various X-ray Telescope X-ray Telescope LaBr3 Detector ESA/NASA ) Current ESA ) Flight ESA ) Projects India ) ESA ) India ESA ESA ESA ESA ESA China /CNES DARPA/ESA ESA/DLR/Swedish Space Agency Operational : Swift, XMM-Newton, Chandra, MSG I and II, (Envisat) Hyperspectral Imaging Updated: 11/10/12 Issue 1 Copyright M.R. Sims 2012 7 Space Research Centre Hyperspectral vs. Multispectral Imaging: I Principles: Image a target in a number of discrete bands over a given wavelength band UV, Visible, NIR, SWIR, LWIR, (Tera-hertz) Known source, natural or artificial broad or narrow band Look at reflectance spectrum Characteristics of target change “reflected” light Unique signatures of objects, chemicals, features and substances may become visible Hyperspectral vs Multispectral: Multispectral: number of discrete bands not necessarily continuous coverage in wavelength, ~>10nm width (visible) Hyperspectral: Continuous coverage high resolution ~2-5nm (visible) Can be enhanced in some cases by a wavelength tunable light source Hyperspectral Imaging Updated: 11/10/12 Issue 1 Copyright M.R. Sims 2012 8 Space Research Centre Hyperspectral vs. Multispectral Imaging: II Issues: Large data-sets Understanding what you are seeing Analysis Expense (of system) Advantages: Non-contact Unique signatures may present themselves Many applications Hyperspectral Imaging Updated: 11/10/12 Issue 1 Copyright M.R. Sims 2012 9 Space Research Centre Hyperspectral vs. Multispectral Imaging: III Applications: Defence/Security Precision Agriculture Earth Resources Pollution Control Plastics/Recycling Pharma Art, Antiquities Ecology Food Forensics Healthcare Research ++…………… Hyperspectral Imaging Updated: 11/10/12 Issue 1 10 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Imaging Data Large data sets consisting of images at each wavelength band, possibly 10-100’s GB Depending on spectral and spatial resolution Each image pixel has a “n” point spectrum associated with it Data called a image cube and sometimes incorrectly a “hypercube” Complex data analysis e.g. PCA may be needed to identify “target” May need to correct for atmospheric Absorption as well illumination source spectrum Image Credit “Why Use Hyperspectral Imaging? Peg Shippert Photgrammetric Engineering and Remote Sensing, April 2004, p377 Hyperspectral Imaging Updated: 11/10/12 Issue 1 11 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Techniques Need to spectrally disperse data from a image pixel Need an detector (single pixel or ideally imaging 2-d array) Need to scan spatially and/or spectrally to collect full data set e.g. Whiskbroom or Pushbroom Scanning can be achieved via moving mirrors or imager Spectral dispersion can be achieved via gratings, linear variable filters, tunable band pass filters (filter wedges), spectrometers, prisms Image Credit Hyperspectrum News Letter http://www.techexpo.com/WWW/opto-knowledge/hyperspectrum/hypersp4.html (a), (b) multispectral (c), (d) hyperspectral Hyperspectral Imaging Updated: 11/10/12 Issue 1 12 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: I Defence/Security Security LWIR Credit: Holma, H., (May 2011) Thermische Hyperspektralbildgebung im langwelligen Infrarot, Photonik Remote chemical imaging of a simultaneous release of SF6 and NH3 at 1.5km using the Telops Hyper-Cam imaging spectrometer Credit: M. Chamberland, V. Farley, A. Vallières, L. Belhumeur, A. Villemaire, J. Giroux et J. Legault, "HighPerformance Field-Portable Imaging Radiometric Spectrometer Technology For Hyperspectral imaging Applications” Proc. SPIE 5994, 59940N, September 2005 Hyperspectral Imaging Updated: 11/10/12 Issue 1 13 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: II Precision Agriculture Stress detection (lack of water) via chlorophyll content (Credit: USDA, SpecTIR web site) Earth Resources Identification of Mineral deposits e.g USGS survey of Afghanistan (Credit USGS) Hyperspectral Imaging Updated: 11/10/12 Issue 1 14 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: III Pollution Control Detection of pollutants e.g. oil leak Credit: http://www.resonon.com/application_ecology.html Below (Credit) from “Hyperspectral Image Analysis for Oil Spill Mitigation” F. Salem and M. Kafatos, paper at 2001 22nd Asian Conference on Remote Sensing 5-9 November 2001 Hyperspectral Imaging Updated: 11/10/12 Issue 1 15 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: IV Plastics/Recycling Detection of clear plastics (Image Credit Resonon Web Site) Pharma Identification of Drugs, QA of Drugs (Image Credit Resonon Web Site) Near infrared identification of two different drug products. Both appear white to the naked eye, however they can be easily distinguished using a Hyperspectral Imaging spectrograph. Hyperspectral Imaging Updated: 11/10/12 Issue 1 16 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: V Art, Antiquities Detection of hidden detail, potentially overcome degradation/aging of materials Detection of mold Detection of earlier works Image Credit “Quantitative Hyperspectral Imaging of Historical Documents: Technique and Applications”, R. Padoan et al. 9th International Conference on NDT of Art, Jerusalem, Israel, 25-30 May 2008 Hyperspectral Imaging Updated: 11/10/12 Issue 1 17 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: VI Forensics Detection of hidden evidence, body fluids, buried bodies, GSR, Forgery, Counterfeit items etc. Tunable light source may be useful Right and middle images Credit ChemImage Left image University of Leicester Hyperspectral Imaging Updated: 11/10/12 Issue 1 18 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: VII Food Detection of mold/degradation Detection of damage e.g. bruises on fruit Classification of quality e.g. meat Image Credit “Prediction of Meat Quality: Application of hyperspectral and Raman Spectroscopy” Moss et al. Report CMS/REP/114446/1 http://www.eblex.org.uk/documents/content/research/rd_qs_b_c_fr_-_nirhyperspectralimagingtopredictbeefquality_191010.pdf Hyperspectral Imaging Updated: 11/10/12 Issue 1 19 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: VIII Ecology Land Use Change Climate Change (effects on plants, environment, estimate of carbon area index m2m-2 , canopy water content) Detection of illegal logging Detection of disease e.g. diseased trees Detection of invasive species (plants, animals (latter if they affect plants, environment) Hyperspectral Imaging Updated: 11/10/12 Issue 1 20 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: IX Planetary Science : I Detect geo-chemistry (mineralogy) of planetary surfaces Based mainly in IR as that is where key absorptions occur Data load can be a problem Currently used from Orbit Examples CRISM NASA Mars Reconnaissance Orbiter In future on-ground e.g. MicroOmega IR hyperspectral microscope on ESA ExoMars 2018 rover for mineral classification Note only samples top surface of any rock outcrop, question mark over how much this represents underlying geology Need an extensive library of spectra and pattern matching Planetary Science: II Hyperspectral Imaging Updated: 11/10/12 Issue 1 Copyright M.R. Sims 2012 21 Space Research Centre Hyperspectral Applications: X Images courtesy CRISM, NASA JPL Hyperspectral Applications: XI Copyright M.R. Sims 2012 Hyperspectral Imaging Updated: 11/10/12 Issue 1 22 Space Research Centre Images Courtesy CRISM, NASA JPL Hyperspectral Imaging Updated: 11/10/12 Issue 1 23 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications:XII Healthcare I Non-invasive technique Both visible and NIR, can see into body “~700-900nm window “ Examples: Skin Cancer Image Courtesy University of Leicester DDU Wound Healing Many studies use limited numbers of patients University of Leicester has set up a Non-Invasive Diagnostics Development Unit (DDU) in conjunction with Leicester Royal Infirmary and Local NHS Trust to pursue start of the art techniques including hyper-spectral (visible) Based in accident and emergency resuscitation bay Want to look at real clinical use Hyperspectral Imaging Updated: 11/10/12 Issue 1 24 Copyright M.R. Sims 2012 Space Research Centre Hyperspectral Applications: XIII Healthcare: II Initial Study 500 patients 20 most common presenting complaints e.g. breathlessness, chest pain No hyper-spectral, but TIR Applying for ethics approval for hyper-spectral work Initial planned studies: Kidney, Liver, Bruising, Skin Lesions Data shows blood distribution using a multi-spectral imager Background Signal Image Courtesy University of Leicester DDU Hyperspectral Hyperspectral Imaging Applications: XIV Updated: 11/10/12 Issue 1 Copyright M.R. Sims 2012 Healthcare: III 25 Space Research Centre Diagnostic Development Unit Equipment Image Courtesy University of Leicester DDU Hyperspectral Imaging Updated: 11/10/12 Issue 1 Copyright M.R. Sims 2012 26 Space Research Centre Concluding Remarks General Remarks Hyper-spectral imaging is a growing area Many applications, an ever growing list Many companies related to topic now in existence: hardware, data processing and applications Costs are reducing and it is no longer just a research or defence/security tool IR hyperspectral remains comparatively expensive Data processing can be an issue Understanding the data is needed by the user – skilled expertise may still be needed in many applications to process and interpret the data Need other data to complement data obtained from hyper-spectral The Future Development of further applications Growth of field and companies associated with it Hyperspectral Imaging Updated: 11/10/12 Issue 1 Copyright M.R. Sims 2012 27 Space Research Centre Acknowledgements Photonex 2012 for hosting this event Prof. Steve Marshall, Gilden Photonics Ltd. and Photonex for the invite You for attending Various companies, institutes as credited on slides for images and information University of Leicester My contact details are e-mail: mrs@le.ac.uk , tel: 0116 2523513 Please enjoy the Conference and Visit the Exhibitors Stands Thank You for Listening