Dose Course 2018_Flipping book
Scanner homogeneity
▪ Pixel value varies with position on the scanner plate due to light scattering differences:
0,9933
relative pixel value
position
▪ small effects (<1%) when moving films parallel to scan direction ▪ up to 8% variation when moving films perpendicular to the scan direction, dose dependent. <2% within 5 cm from the scanner axis for D<2Gy)
1,0001
0,9273
0,9891
1
0,9859
0,9237
0,9992
Scan direction
▪
2D correction for “full” films
0,9939
▪
Dose dependent
▪
Scanner dependent
EPSON Pro 1680 Expression scanner:
Paelinki et al PMB 52 (2007) and Fuss et al PMB 52 (2007)
Fiandra et al MP 33 (2006)
Epson 10000XL scanner :
Scan direction
Ferreira et al. PMB54 (2009)
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