In this work, we studied how the detector angle affects the signal-to-noise ratio (S/N) of X-ray fluorescence CT (XFCT), which is a major factor in reducing background noise and improving the detection sensitivity. We simulated a benchtop multi-pinhole XFCT system including a fan-beam x-ray source, a phantom (2.5 cm in diameter) consisting of one insert with gold nanoparticles (GNPs) , 2-sided multi-pinhole (3 pinholes) collimator aimed to acquire multiple projections simultaneously and 2-sided two-dimensional (2D) detector based on Geant4. The signal and noise were defined as the emitted Kα1=68.8keV X-ray fluorescence and Compton scatter fluorescence, respectively. The result was evaluated in three approaches at four different detector angles 60° (forward-scatter), 90° (side-scatter), 120° and 150° (back-scatter). In the simulation, the tube voltage was set to 90,100,110 and 120keV with fixed GNPs concentration (2%) and insert diameter (6mm).Then, the GNPs concentration was increased from 0.25%, 0.5%, 1% to 2% with fixed tube voltage (120keV) and insert diameter (6mm). Next, the insert diameter was set to 4, 6, 8, and 10mm with fixed tube voltage (120keV) and GNPs concentration (1%). The optimized detection angle was acquired by comparing the correlation between S/N and detector angles in terms of tube voltage, GNPs concentration and insert diameter. The experimental results demonstrated that, for most circumstances, the highest S/N could be obtained when detector angle was set to 120°.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.