IMAGE RECEPTORSIMAGE RECEPTORS

Follow the Sequence- Film SystemFollow the Sequence- Film System

TubeTube PatientPatient (bucky) or non-bucky (bucky) or non-bucky CassetteCassette INTENSIFYING SCREEN INTENSIFYING SCREEN FILM FILM

Follow the Sequence- Filmless (CR) Follow the Sequence- Filmless (CR) SystemSystem

TubeTube PatientPatient (bucky) or non-bucky (bucky) or non-bucky CassetteCassette IMAGING PLATE IMAGING PLATE DIGITIZER OR READERDIGITIZER OR READER MONITORMONITOR

Follow the Sequence- Filmless (DR) Follow the Sequence- Filmless (DR) SystemSystem

TubeTube PatientPatient (bucky) or non-bucky (bucky) or non-bucky DIGITAL RECEPTORDIGITAL RECEPTOR MONITORMONITOR

INTENSIFYING SCREENINTENSIFYING SCREEN PG 179PG 179 When using intensifying screens in cassette the When using intensifying screens in cassette the

exposure to the film is 90% -99% FROM exposure to the film is 90% -99% FROM LIGHTLIGHT

Anatomy of a screenAnatomy of a screen Protective layerProtective layer Phosphor or active layerPhosphor or active layer Reflecting or absorbing layerReflecting or absorbing layer basebase

PHOSPHORSPHOSPHORS SPECTRAL EMISSIONSPECTRAL EMISSION RARE EARTHRARE EARTH HIGH ABSORPTION +HIGH HIGH ABSORPTION +HIGH

CONVERSION EFFICIENCY=CONVERSION EFFICIENCY= FASTER SPEEDFASTER SPEED

PHOSPHOR THICKNESS, SIZEPHOSPHOR THICKNESS, SIZE Impacts screen speed and detailImpacts screen speed and detail Faster screen =less detail = less mAsFaster screen =less detail = less mAs Slower screen = more detail =more mAs Slower screen = more detail =more mAs Old screen speed/new screen speedOld screen speed/new screen speed Reflecting layers = increase screen speedReflecting layers = increase screen speed Light absorbing layer or light absorbing Light absorbing layer or light absorbing

dyes=decrease speed but increase recorded detaildyes=decrease speed but increase recorded detail Table 7-9Table 7-9 Quantum Mottle Quantum Mottle Screen MaintenanceScreen Maintenance

Follow the Sequence- Filmless (CR) Follow the Sequence- Filmless (CR) SystemSystem

TubeTube PatientPatient (bucky) or non-bucky (bucky) or non-bucky CassetteCassette IMAGING PLATE IMAGING PLATE DIGITIZER OR READERDIGITIZER OR READER MONITORMONITOR

CR cassetteCR cassette Protective layerProtective layer Photostimulable phosphorPhotostimulable phosphor Reflective layerReflective layer BaseBase BackingBacking

Barium Fluorohalide crystals coated Barium Fluorohalide crystals coated with europiumwith europium

Phosphor releases some visible lightPhosphor releases some visible light The x-ray energy is absorbed (trapped)The x-ray energy is absorbed (trapped) Latent imageLatent image Sensitive to a wide range of energiesSensitive to a wide range of energies Erase plate if not used in 48 hoursErase plate if not used in 48 hours Process within an hour of exposureProcess within an hour of exposure Increase mAs as CR is equivalent to 200 screen speed Increase mAs as CR is equivalent to 200 screen speed

vs 400 screen speed used in film systems…why? vs 400 screen speed used in film systems…why?

Follow the Sequence- Filmless (DR) Follow the Sequence- Filmless (DR) SystemSystem

TubeTube PatientPatient (bucky) or non-bucky (bucky) or non-bucky DIGITAL RECEPTORDIGITAL RECEPTOR MONITORMONITOR

DIRECT CAPTURE DETECTORDIRECT CAPTURE DETECTOR TFT –Thin film transistors –flat panel consists of TFT –Thin film transistors –flat panel consists of

detectors and TFT’sdetectors and TFT’s Radiation interacts with the detector (within the table, Radiation interacts with the detector (within the table,

upright chest unit or on a extremity unit)upright chest unit or on a extremity unit) X-rays are either converted to light that reacts to a X-rays are either converted to light that reacts to a

layer of amorphous silver = electric chargeCCD layer of amorphous silver = electric chargeCCD (CHARGE COUPLED DEVICE)(CHARGE COUPLED DEVICE)

OrOr X-rays are interact directly with layer of amorphous X-rays are interact directly with layer of amorphous

silver = electric chargesilver = electric charge