A wide dynamic range, high-spatial-resolution scanning system for radiochromic dye films.
This paper describes the evaluation of an inexpensive, commercially available 35 mm transparency slide scanner as a potential alternative scanning device for GafChromic HD-810 radiochromic dye film. Besides its low cost, the principal advantages of this type of scanner are high spatial resolution and high speed (a typical scan taking less than 1 min). With broad-band illumination the useful dose range using grey-scale imaging of GafChromic HD-810 is limited to about 50-800 Gy. By using the colour-scale imaging capability of the scanner we have been able to achieve a significant extension covering a similar range (15-2000 Gy) to that attainable using monochromatic illumination. The short-term reproducibility of the system is good, with a coefficient of variation of doses estimated from repeat scanning of uniformly exposed calibration films of less than 2%. Long-term stability is ensured by the scanning of a manufacturer-supplied test slide. The slide scanner system has been used in the determination of depth dose distributions from a model 'hot particle' source containing 106Ru/Rh. GafChromic dye film stacks irradiated by the source were read out on both the slide scanner and a conventional Joyce Loebl MDM6 scanning stage microdensitometer. The overall agreement between the dose estimates provided by the two systems was within 10%.
Aydarous
A S
AS
School of Physics and Astronomy, The University of Birmingham, Edgbaston, UK. A.Aydarous@bham.ac.uk
Darley
P J
PJ
Charles
M W
MW
D001610:Beta Particles; D002138:Calibration; D004396:Coloring Agents; D003720:Densitometry / Q000379:methods; D005373:Film Dosimetry; D008027:Light; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D004396:Coloring Agents