Study of Phase-Dispersive X-Ray Imaging Tomomi Ohgaki and Ichita Endo (Hiroshima Univ.) Study of Phase-Dispersive X-Ray Imaging P la n e w a v e X-Ray Imaging Equipments •Absorption Contrast Method （Usual） •Phase Contrast Method For Medical application O b je c t Plane wave passing through the object Early diagnoses of breast cancer Imaging for living soft tissues Cross Section of X-Ray Absorption and Phase Shift Phase Shift Cross Section (cm2) Absorption Phase Contrast X-ray Energy 8.3 keV 13.5keV 24.8keV 62.0keV Atomic Number Phase shift of light elements 1000 times higher than absorption Radiation dose by phase contrast imaging can be reduced. Setup for X-Ray Phase-Dispersive Measurements X-Ray Tube Characteristic X-Ray 60～70 keV Target W,Re,Au M on och ro Monochrometor Silicon single crystal S lit Asymmetric Bragg Diffraction Crystal Analyzer Silicon single crystal X -ray tu b e Higher order diffraction C r yst al Maximum contrast by rotating Crystal analyzer X-Ray Detectors Imaging plate a n a ly z e r several 10mm R Emulsion several mm X-Ray CCD several 10mm Transmission, Reflection X-Ray measurements I g /I i (g=0,h) Reflection and Transmission Intensities 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 I/I 0i I/I hi -5 -4 -3 -2 -1 0 1 2 3 4 5 a W Ka-Line (59.3keV) Crystal analyzer Si(422) thickness 560mm Rotating crystal analyzer a~rotation angle No object case Transmission Intensity 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 1.0 x(mm) W Ka-Line (59.3keV) Crystal analyzer Si(422) thickness 560mm Object (Prism, base 2mm, base angle 45degree) 0 -1.0 1.0 0 -1.0 a df/dx Reflection Intensity 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 1.0 W Ka-Line (59.3keV) Crystal analyzer Si(422) thickness 560mm Object (Prism, base 2mm, base angle 45degree) x(mm) 0 1.0 0 -1.0 -1.0 a Reflection and Transmission Intensities 0.9 0.8 I g /I i (g=0,h) 0.7 W Ka-Line (59.3keV) Crystal analyzer Si(422) thickness 560mm Object (Prism, base 2mm, base angle 45degree) I/I 0i 0.6 0.5 0.4 0.3 I/I hi Dq=-4.8x10-7rad (a=-0.70) 0.2 0.1 0 -1.5 -1.0 -0.5 0 0.5 x (mm) 1.0 1.5 Samples of Phase Contrast Method Veins of leaf (S.Wilkins et al., 1998) Arteries of mouse (V.N.Ingal et al.,1998) Approach to Venture Business Medical application, Electronics, Aerospace, Food industries •Medical diagnoses … breast cancer, malignant tumors •Search for impurity objects in Foods •Study of Biology •Search of oil …fluid mechanics •Investigation of object of art or craft object •Investigation of new materials like ceramics or fiber Simulation by Dynamical Diffraction Theory •Disagreement between analytical formulas and experimental results where df/dx is large changeable. Ｘ-Ray Crystal surface Solve Takagi-Taupin equations using Simulation. Transmission X-Ray Reflection X-Ray Simulation code CPRI Purpose：Calculate Phase Radiological Imaging •X-ray tube or SOR light： Target size, current, voltage •Slit： Transfer matrix •Monochromator： Asymmetric Bragg diffraction •Object： Linear absorption coefficient, refractive index •Crystal analyzer： Takagi-Taupin eqs. •Detector： Detection area, Detection efficiency Intensity of one photon incidence Incident X-Ray Crystal surface Si Crystal In te ns ity 1.0 0 10 Crystal surface 20 S h 30 40 50 0.5 0 0.0 10 20 30 S0 40 50 Intensities by Simulation Transmission Reflection 0.8 Intensity 0.6 0.4 0.2 0.0 -2.0x10 -3 -1.0x10 -3 0.0 1.0x10 X position (m) -3 2.0x10 -3 Prototype experiments コン ピ ュー ター X線 管 X軸 用 モ ノクロ メー ター M o サ ン プ ル 結 晶 分 Prototype Products X-ray P haseC ontrastImaging X-Ray Tube X-Ray Tube 22.5mA 55kV Target Mo Imaging plate Imaging Plate Reader Rigaku R-AXIS-D53 Prototype experiments Asymmetric Bragg Diffraction Ge crystal (115) qB=19.0° qB-a=3.2° b=0.0983 Laue case Ge crystal(220) thickness200mm コ ン ピ ュー ター qB=10.2° X線 管 Mo Ka1-line =0.70920 w=17.480 keV Mo X軸 用 モ ノクロ メー ター サ ン プ ル 結 晶 分 Polypropylene r=0.95g/cm3 Rocking curve from crystal analyzer Laue case Transmission Intensity 6 2.6x10 6 2.4x10 6 2.2x10 6 2.0x10 6 1.8x10 6 1.6x10 6 1.4x10 6 1.2x10 6 1.0x10 5 8.0x10 5 6.0x10 5 4.0x10 5 2.0x10 0.0 -600 Reflection w=295mrad w=329mrad Ge (220) w=27.4mrad qx=820mrad qy=13mrad -400 -200 0 200 400 Rocking Angle (mrad) 600 Transmission Image of Polypropylene q-qB=-160 mrad q-qB=0 mrad q-qB=+160 mrad Intensity Rocking curve from crystal analyzer Bragg case 1.8x10 7 1.6x10 7 1.4x10 7 1.2x10 7 1.0x10 7 8.0x10 6 6.0x10 6 4.0x10 6 2.0x10 6 Reflection w=235mrad Si (220) w=10.9mrad 0.0 -400 -300 -200 -100 0 100 200 Rocking Angle (mrad) 300 400 Reflection Image of Polypropylene q-qB=0 mrad Summary •We have done the prototype experiments for PDI. •We have made the simulation code for PDI. •Now Hiroshima group will study PDI with Betatron. 「位相コントラストX線撮像装置」大垣智巳、遠藤一太、特願2001-203219 (July 11, 2001) "Simulation code for phase radiological imaging using dynamical theory” T.Ohgaki and I.Endo REFER Hiroshima Univ. got RF cavity Beam life time is 4min.
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