Imaging Properties of the Medipix2 Imaging Properties of the Medipix2 System exploiting Single and Dual System exploiting Single and Dual Energy Thresholds Energy Thresholds L. Tlustos L. Tlustos 1 1 , R. Ballabriga , R. Ballabriga 1 , , M. Campbell M. Campbell 1 , , E. Heijne E. Heijne 1 , k Kincade , k Kincade 2 , X. Llopart , X. Llopart 1 , P. , P. Stejskal Stejskal 3 1 1 Ph Department, CERN, Geneva, Switzerland Ph Department, CERN, Geneva, Switzerland 2 University of Canterbury, Christchurch, University of Canterbury, Christchurch, New Zealand New Zealand 3 Institute of Experimental and Applied Institute of Experimental and Applied Physics, Technical University of Prague, Physics, Technical University of Prague, Czech Republic. Czech Republic.
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Imaging Properties of the Medipix2 System Imaging Properties of the Medipix2 System exploiting Single and Dual Energy exploiting Single and Dual Energy
ThresholdsThresholds
L. TlustosL. Tlustos11, R. Ballabriga, R. Ballabriga11, , M. CampbellM. Campbell11, E. Heijne, E. Heijne11, k , k KincadeKincade22, X. Llopart, X. Llopart11, P. Stejskal, P. Stejskal33
1 1 Ph Department, CERN, Geneva, SwitzerlandPh Department, CERN, Geneva, Switzerland22 University of Canterbury, Christchurch, New Zealand University of Canterbury, Christchurch, New Zealand33 Institute of Experimental and Applied Physics, Institute of Experimental and Applied Physics, Technical University of Prague, Czech Republic. Technical University of Prague, Czech Republic.
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The Medipix2 ConsortiumThe Medipix2 Consortium Institut de Fisca d'Altes Energies, Barcelona, Spain Institut de Fisca d'Altes Energies, Barcelona, Spain University of Cagliari and INFN Section thereof, ItalyUniversity of Cagliari and INFN Section thereof, Italy CEA, Paris, FranceCEA, Paris, France CERN, Geneva, Switzerland, CERN, Geneva, Switzerland, Universitat Freiburg, Freiburg, Germany, Universitat Freiburg, Freiburg, Germany, University of Glasgow, ScotlandUniversity of Glasgow, Scotland Universita' di Napoli and INFN Section thereof, ItalyUniversita' di Napoli and INFN Section thereof, Italy NIKHEF, Amsterdam, The NetherlandsNIKHEF, Amsterdam, The Netherlands University of Pisa and INFN Section thereof, ItalyUniversity of Pisa and INFN Section thereof, Italy University of Auvergne, Clermont Ferrand, France, University of Auvergne, Clermont Ferrand, France, Laboratory of Molecular Biology, Cambridge EnglandLaboratory of Molecular Biology, Cambridge England Mitthogskolan, Sundsvall, Sweden, Mitthogskolan, Sundsvall, Sweden, Czech Technical University, Prague, Czech RepublicCzech Technical University, Prague, Czech Republic ESRF, Grenoble, FranceESRF, Grenoble, France Academy of Sciences of the Czech Republic, PragueAcademy of Sciences of the Czech Republic, Prague Universität Erlangen-Nurnberg, Erlangen, GermanyUniversität Erlangen-Nurnberg, Erlangen, Germany University of California, Berkeley, USAUniversity of California, Berkeley, USA
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OutlineOutline
Motivation and a brief overview of the Motivation and a brief overview of the Medipix2 systemMedipix2 system
MTF, NPS and DQE for a single photon MTF, NPS and DQE for a single photon counting system as a function of lower counting system as a function of lower threshold threshold
Imaging of an object using the energy Imaging of an object using the energy window window
Concluding remarksConcluding remarks
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Introduction and MotivationIntroduction and Motivation
Single photon counting provides clean images Single photon counting provides clean images across a wide range of incoming photon fluxes across a wide range of incoming photon fluxes
Flexible – many applicationsFlexible – many applications
Energy selective x-ray imaging possibleEnergy selective x-ray imaging possible
MTF, NPS and DQE as a function of threshold - MTF, NPS and DQE as a function of threshold - Medipix2 readout chip and a 300 Medipix2 readout chip and a 300 m thick Si sensor m thick Si sensor
First energy selective images of an object using a First energy selective images of an object using a polychromatic sourcepolychromatic source
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Hybrid Pixel Detector Hybrid Pixel Detector
Detector and electronics readout are optimized separately
Charge sensitive preamplifier with individual leakage current compensation2 discriminators with globally adjustable threshold3-bit local fine tuning of the threshold per discriminator1 test and1 mask bitExternal shutter activates the counter13-bit pseudo-random counter1 Overflow bit
Concluding remarksConcluding remarks The Medipix2 system offers clean particle The Medipix2 system offers clean particle
imagingimaging MTF is typically 70% at pixel pitch. This can MTF is typically 70% at pixel pitch. This can
be enhanced by increasing threshold but at be enhanced by increasing threshold but at the expense of DQEthe expense of DQE
Energy window measurements provide Energy window measurements provide insight into environmentinsight into environment
Quantitative evaluation of the imaging Quantitative evaluation of the imaging properties using the energy window in properties using the energy window in preparationpreparation
Maybe the window should be used to Maybe the window should be used to exclude given energies!exclude given energies!
And finally, a message for those who doubt And finally, a message for those who doubt the future of photon counting energy the future of photon counting energy sensitive imaging systems….. sensitive imaging systems…..
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……the clock is ticking!the clock is ticking!
< 1 frame/sec. Limited by DAQ software
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AcknowledgementsAcknowledgements
Fellow members of the Medipix ConsortiumFellow members of the Medipix Consortium www.cern.ch/medipix
Colleagues from Nikhef for Muros2 readout system Colleagues from Nikhef for Muros2 readout system J. Visschers H. Verkooijen
Colleagues the Naples group for Medisoft4.0Colleagues the Naples group for Medisoft4.0 P. Russo G. Mettivier M.C. Montesi
