Laser scanning and visible light transmission imaging of polymer gel dosimeters

DAVID CHACÓN; MARCELO ROMERO; FACUNDO MATTEA; MAURO VALENTE

Córdoba

Simposio; 14th International Symposium on Radiation Physics (ISRP-14).; 2018

Oral Presentation: Advances in ionizing radiation medical applications go hand in hand with the development of dosimetry systems. Gel dosimeters represent one of these remarkable examples being not only capable of measuring absorbed dose, but also obtain dose distributions in three dimensions with high resolution [1] within tissue equivalent materials [2]. Readout methods for dosimetry systems include complex and expensive equipments like magnetic resonance imaging, ultrasound and X-ray tomography. However, it is also possible to use cheaper optical readout methods [3]. The purpose of this work, is to compare two different optical readout systems for polymer gel dosimetry, both of them are specifically designed and home made. The first readout system, already validated [4] is an optical transmission device consisting of a band-pass filtered CCD camera and a uniform visible light illumination by led matrix [4]. The second readout system consists of two photodiodes (bpb10) sensors integrated into an operational amplifier circuit, and a 632nm laser source with a power of 1mW. Additionally, this readout system has an Arduino Mega board to digitize the detected signals and to control its motion system. An example of optical density maps obtained by the laser scanning readout system is presented in figure 1 for a PAGAT dosimeter irradiated with a LINAC 6MV