Image Capture XRay XRay Generation Film Can be
Image Capture
X-Ray
X-Ray Generation
Film Can be exposed directly to x-ray, but sensitivity is very low Topcoat Emulsion Adhesive Base • Nitrate – 1910 s to 1930 s • Acetate – 1920 s to mid 1960 s • Polyester – mid 1950 s to present
Intensifying Screens X-rays Intensifying Screen Intensifies available x-ray light
Film is the detector and storage…. . “The PACS” Film PACS
Digital Imaging • Ultrasound • Nuclear Medicine • Computed Tomography • Magnetic Resonance
Digital Image Capture Computed Radiography
Digital Image Capture - CR • Expose plate • Drop into Reader • PMT scans plate • Converts to Digital • Sends to monitor Secondary Capture DR
Digital Image Capture - CR X-ray Energy Low Energy Imaging Excited Phosphor Plate High Energy
Digital Image Capture - CR Laser Scanning Creating Visible Light, Digital Capture Low Energy Excited Phosphor High Energy
Digital Image Capture - CR Bright White Light Low Energy Excited Phosphor High Energy
Digital Image Capture Flat Panel Detector
Image Capture - DR • Flat Panel Detector • Image info captured • Converts to Digital • Sends to monitor
Flat Panel Technology - Cross Section Discussion of Cs. I vs. GOS X-rays Cs. I GOS Photodiode TFT Array Csi focuses scintillator light to TFT High Image quality GOs scatters produced light to TFT causing reduced image quality
Technology Review
Flat Panel Technology - Cross Section
Digital Image Capture - Flat Panel X-ray Energy Low Energy High Energy 8 Million
Digital Image Capture - Flat Panel X-ray Energy Low Energy High Energy 8 Million
Digital Radiography Performance
Imaging Performance 4096 s r o pt e c e gi i D R l ta
Speed 4096 s r o pt e c e gi i D R l ta
Digital Radiography
Image Generation - Today Using 100 yr old technology……Vacuum Tubes • • Heats a negatively charged metal filament to 1000º C Combination of heat and charge releases electrons Strikes a positively charged electrode X-rays created by the energy of the impact
Image Generation - Future Electron Field Emission • A myriad of carbon nano-tubes on a platform • Compact source of x-rays that can be controlled with great precision, built into an array • Each element programmed to fire when required
u o Y k n Tha
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