Coded aperture imager with depth of interaction scintillators

Taewoong Lee, Hyounggun Lee, Won Ho Lee

Research output: Contribution to journalArticle

Abstract

In this study, a coded-aperture imager with a depth of interaction (DOI) detector was designed and its performance was evaluated using a Monte Carlo simulation. The DOI coded-aperture imager consisted of a modified uniformly redundant array (MURA) and four layers of a 16 × 16 matrix of 2 mm cubic scintillators. To improve its performance, the reconstructed images from each layer were combined using a hybrid maximum likelihood expectation maximization (h-MLEM) technique. The DOI coded-aperture imager demonstrated higher signal-to-noise ratios (SNRs) in the reconstructed images, when compared with conventional coded-aperture imagers with 2D pixelated scintillators. In addition, various types of scintillators were tested and compared with respect to their RV curves, detection efficiencies, and SNRs. Among the tested scintillators, gadolinium aluminum gallium garnet (GAGG) demonstrated the highest performance above 356 keV. However, for low-energy radiation (< 200 keV), the performance of all the scintillators were similar. Because the timing resolution is shorter than those of other scintillators, LaBr3 could show a relatively high performance for measurement in high background conditions.

Fingerprint

Image sensors
Phosphors
scintillation counters
apertures
interactions
Signal to noise ratio
signal to noise ratios
Gadolinium
Garnets
Gallium
gadolinium
garnets
Maximum likelihood
gallium
time measurement
Detectors
aluminum
Aluminum
Radiation
detectors

Keywords

  • DOI coded aperture imager
  • Hybrid update maximum likelihood expectation maximization (h-MLEM)

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Instrumentation

Cite this

@article{396f6b19675b4333b7abfc6032afa358,
title = "Coded aperture imager with depth of interaction scintillators",
abstract = "In this study, a coded-aperture imager with a depth of interaction (DOI) detector was designed and its performance was evaluated using a Monte Carlo simulation. The DOI coded-aperture imager consisted of a modified uniformly redundant array (MURA) and four layers of a 16 × 16 matrix of 2 mm cubic scintillators. To improve its performance, the reconstructed images from each layer were combined using a hybrid maximum likelihood expectation maximization (h-MLEM) technique. The DOI coded-aperture imager demonstrated higher signal-to-noise ratios (SNRs) in the reconstructed images, when compared with conventional coded-aperture imagers with 2D pixelated scintillators. In addition, various types of scintillators were tested and compared with respect to their RV curves, detection efficiencies, and SNRs. Among the tested scintillators, gadolinium aluminum gallium garnet (GAGG) demonstrated the highest performance above 356 keV. However, for low-energy radiation (< 200 keV), the performance of all the scintillators were similar. Because the timing resolution is shorter than those of other scintillators, LaBr3 could show a relatively high performance for measurement in high background conditions.",
keywords = "DOI coded aperture imager, Hybrid update maximum likelihood expectation maximization (h-MLEM)",
author = "Taewoong Lee and Hyounggun Lee and Lee, {Won Ho}",
year = "2019",
month = "1",
day = "1",
doi = "10.1016/j.nima.2019.01.010",
language = "English",
journal = "Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment",
issn = "0168-9002",
publisher = "Elsevier",

}

TY - JOUR

T1 - Coded aperture imager with depth of interaction scintillators

AU - Lee, Taewoong

AU - Lee, Hyounggun

AU - Lee, Won Ho

PY - 2019/1/1

Y1 - 2019/1/1

N2 - In this study, a coded-aperture imager with a depth of interaction (DOI) detector was designed and its performance was evaluated using a Monte Carlo simulation. The DOI coded-aperture imager consisted of a modified uniformly redundant array (MURA) and four layers of a 16 × 16 matrix of 2 mm cubic scintillators. To improve its performance, the reconstructed images from each layer were combined using a hybrid maximum likelihood expectation maximization (h-MLEM) technique. The DOI coded-aperture imager demonstrated higher signal-to-noise ratios (SNRs) in the reconstructed images, when compared with conventional coded-aperture imagers with 2D pixelated scintillators. In addition, various types of scintillators were tested and compared with respect to their RV curves, detection efficiencies, and SNRs. Among the tested scintillators, gadolinium aluminum gallium garnet (GAGG) demonstrated the highest performance above 356 keV. However, for low-energy radiation (< 200 keV), the performance of all the scintillators were similar. Because the timing resolution is shorter than those of other scintillators, LaBr3 could show a relatively high performance for measurement in high background conditions.

AB - In this study, a coded-aperture imager with a depth of interaction (DOI) detector was designed and its performance was evaluated using a Monte Carlo simulation. The DOI coded-aperture imager consisted of a modified uniformly redundant array (MURA) and four layers of a 16 × 16 matrix of 2 mm cubic scintillators. To improve its performance, the reconstructed images from each layer were combined using a hybrid maximum likelihood expectation maximization (h-MLEM) technique. The DOI coded-aperture imager demonstrated higher signal-to-noise ratios (SNRs) in the reconstructed images, when compared with conventional coded-aperture imagers with 2D pixelated scintillators. In addition, various types of scintillators were tested and compared with respect to their RV curves, detection efficiencies, and SNRs. Among the tested scintillators, gadolinium aluminum gallium garnet (GAGG) demonstrated the highest performance above 356 keV. However, for low-energy radiation (< 200 keV), the performance of all the scintillators were similar. Because the timing resolution is shorter than those of other scintillators, LaBr3 could show a relatively high performance for measurement in high background conditions.

KW - DOI coded aperture imager

KW - Hybrid update maximum likelihood expectation maximization (h-MLEM)

UR - http://www.scopus.com/inward/record.url?scp=85060278502&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85060278502&partnerID=8YFLogxK

U2 - 10.1016/j.nima.2019.01.010

DO - 10.1016/j.nima.2019.01.010

M3 - Article

AN - SCOPUS:85060278502

JO - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

JF - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

SN - 0168-9002

ER -