León-Marroquín EY, García-Garduño OA, Camacho-López MÁ

Language: Spanish
References: 22
Page: 38-43
PDF size: 129.70 Kb.

ABSTRACT

Objective: characterization of radiochromic film EBT2 (RF-EBT2) with three different optical systems (OS): scanner, spectrophotometer and laser. Material and methods: the RF-EBT2 films were irradiated at different dose levels with a linear accelerator of a nominal energy of 6 MV and analyzed with three different OS. The film characterization consists of calibration curves, absorption and polarization spectrum. Results: in the analysis of absorption spectrum, it was found two absorptions peaks centered at 585 nm and 636nm, their positions are not dose dependent within the dose range studied. The optical density increases as the dose level increases. However, the increment depends on the wavelength at which it is measured. The polarization effect shows that change in optical density decreases as the dose increases. Finally, the calibration curve shows different sensitivity levels with each OS, nerveless the spectrophotometer presents higher film response. Conclusion: it is possible to use a spectrophotometer and a laser to analyze the response of RF-EBT2 wíth the advantage that the response of the film is orientation independent for these OS compared with a commercial flatbed scanner.

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