Date post: | 03-Jan-2016 |
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Image Capture
X-Ray
X-Ray Generation
Film
Can be exposed directly to x-ray, but sensitivity is very low
• Nitrate – 1910s to 1930s• Acetate – 1920s to mid 1960s• Polyester – mid 1950s to present
TopcoatEmulsionAdhesive
Base
Intensifying Screens
Intensifying Screen
Intensifying Screen
Intensifies available x-ray light
X-rays
Film PACS
Film is the detector and storage…..“The PACS”
Digital Imaging
• Ultrasound
• Nuclear Medicine
• Computed Tomography
• Magnetic Resonance
Computed Radiography
Digital Image Capture
• Expose plate
• Drop into Reader
• PMT scans plate
• Converts to Digital
• Sends to monitor
Secondary Capture DR
CR is Digital
Digital Image Capture - CR
Imaging PlateExcited Phosphor High Energy
Low Energy
X-ray Energy
Digital Image Capture - CR
High Energy
Low Energy
Laser Scanning
Creating Visible Light, Digital Capture
Excited Phosphor
Digital Image Capture - CR
High Energy
Low Energy
Bright White Light
Excited Phosphor
Digital Image Capture - CR
Flat Panel Detector
Digital Image Capture
Image Capture - DR
• Flat Panel Detector
• Image info captured
• Converts to Digital
• Sends to monitor
DR is Digital
TFT Array
CsI
Photodiode
X-rays
TFT Array
GOS
Photodiode
X-rays
Discussion of CsI vs. GOS
Csi focuses scintillator light to TFT
High Image quality
GOs scatters produced light to TFT causing reduced image quality
Flat Panel Technology - Cross Section
Technology Review
Flat Panel Technology - Cross Section
Digital Image Capture - Flat Panel
8 Million
X-ray Energy
High Energy
Low Energy
High Energy
Low Energy
X-ray Energy
8 Million
Digital Image Capture - Flat Panel
Digital Radiography
Performance
4096
Imaging Performance
Digital R
eceptors
4096
Speed
Digital R
eceptors
Digital Radiography
Image Generation - Today
Using 100 yr old technology……Vacuum Tubes
• Heats a negatively charged metal filament to1000º 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
Thank You