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Title: Spectral analysis of fundamental signal and noise performances in photoconductors for mammography

Abstract

Purpose: This study investigates the fundamental signal and noise performance limitations imposed by the stochastic nature of x-ray interactions in selected photoconductor materials, such as Si, a-Se, CdZnTe, HgI{sub 2}, PbI{sub 2}, PbO, and TlBr, for x-ray spectra typically used in mammography. Methods: It is shown how Monte Carlo simulations can be combined with a cascaded model to determine the absorbed energy distribution for each combination of photoconductor and x-ray spectrum. The model is used to determine the quantum efficiency, mean energy absorption per interaction, Swank noise factor, secondary quantum noise, and zero-frequency detective quantum efficiency (DQE). Results: The quantum efficiency of materials with higher atomic number and density demonstrates a larger dependence on convertor thickness than those with lower atomic number and density with the exception of a-Se. The mean deposited energy increases with increasing average energy of the incident x-ray spectrum. HgI{sub 2}, PbI{sub 2}, and CdZnTe demonstrate the largest increase in deposited energy with increasing mass loading and a-Se and Si the smallest. The best DQE performances are achieved with PbO and TlBr. For mass loading greater than 100 mg cm{sup -2}, a-Se, HgI{sub 2}, and PbI{sub 2} provide similar DQE values to PbO and TlBr. Conclusions:more » The quantum absorption efficiency, average deposited energy per interacting x-ray, Swank noise factor, and detective quantum efficiency are tabulated by means of graphs which may help with the design and selection of materials for photoconductor-based mammography detectors. Neglecting the electrical characteristics of photoconductor materials and taking into account only x-ray interactions, it is concluded that PbO shows the strongest signal-to-noise ratio performance of the materials investigated in this study.« less

Authors:
; ; ; ;  [1]
  1. School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, Republic of Korea and Center for Advanced Medical Engineering Research, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22098841
Resource Type:
Journal Article
Journal Name:
Medical Physics
Additional Journal Information:
Journal Volume: 39; Journal Issue: 5; Other Information: (c) 2012 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0094-2405
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 62 RADIOLOGY AND NUCLEAR MEDICINE; BIOMEDICAL RADIOGRAPHY; CADMIUM COMPOUNDS; COMPUTERIZED SIMULATION; ENERGY ABSORPTION; ENERGY SPECTRA; LEAD IODIDES; LEAD OXIDES; MAMMARY GLANDS; MERCURY IODIDES; MONTE CARLO METHOD; NOISE; QUANTUM EFFICIENCY; SEMICONDUCTOR DETECTORS; SIGNAL-TO-NOISE RATIO; SILICON; TELLURIUM COMPOUNDS; X RADIATION; X-RAY SPECTRA; ZINC COMPOUNDS

Citation Formats

Kim, Ho Kyung, Lim, Chang Hwy, Tanguay, Jesse, Yun, Seungman, Cunningham, Ian A., School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, 100 Perth Drive, London, Ontario N6A 5K8, School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, 100 Perth Drive, London, Ontario N6A 5K8. Spectral analysis of fundamental signal and noise performances in photoconductors for mammography. United States: N. p., 2012. Web. doi:10.1118/1.3702455.
Kim, Ho Kyung, Lim, Chang Hwy, Tanguay, Jesse, Yun, Seungman, Cunningham, Ian A., School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, 100 Perth Drive, London, Ontario N6A 5K8, School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, & Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, 100 Perth Drive, London, Ontario N6A 5K8. Spectral analysis of fundamental signal and noise performances in photoconductors for mammography. United States. https://doi.org/10.1118/1.3702455
Kim, Ho Kyung, Lim, Chang Hwy, Tanguay, Jesse, Yun, Seungman, Cunningham, Ian A., School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, 100 Perth Drive, London, Ontario N6A 5K8, School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735, and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, 100 Perth Drive, London, Ontario N6A 5K8. Tue . "Spectral analysis of fundamental signal and noise performances in photoconductors for mammography". United States. https://doi.org/10.1118/1.3702455.
@article{osti_22098841,
title = {Spectral analysis of fundamental signal and noise performances in photoconductors for mammography},
author = {Kim, Ho Kyung and Lim, Chang Hwy and Tanguay, Jesse and Yun, Seungman and Cunningham, Ian A. and School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, 100 Perth Drive, London, Ontario N6A 5K8 and School of Mechanical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 and Imaging Research Laboratories, Robarts Research Institute, University of Western Ontario, 100 Perth Drive, London, Ontario N6A 5K8},
abstractNote = {Purpose: This study investigates the fundamental signal and noise performance limitations imposed by the stochastic nature of x-ray interactions in selected photoconductor materials, such as Si, a-Se, CdZnTe, HgI{sub 2}, PbI{sub 2}, PbO, and TlBr, for x-ray spectra typically used in mammography. Methods: It is shown how Monte Carlo simulations can be combined with a cascaded model to determine the absorbed energy distribution for each combination of photoconductor and x-ray spectrum. The model is used to determine the quantum efficiency, mean energy absorption per interaction, Swank noise factor, secondary quantum noise, and zero-frequency detective quantum efficiency (DQE). Results: The quantum efficiency of materials with higher atomic number and density demonstrates a larger dependence on convertor thickness than those with lower atomic number and density with the exception of a-Se. The mean deposited energy increases with increasing average energy of the incident x-ray spectrum. HgI{sub 2}, PbI{sub 2}, and CdZnTe demonstrate the largest increase in deposited energy with increasing mass loading and a-Se and Si the smallest. The best DQE performances are achieved with PbO and TlBr. For mass loading greater than 100 mg cm{sup -2}, a-Se, HgI{sub 2}, and PbI{sub 2} provide similar DQE values to PbO and TlBr. Conclusions: The quantum absorption efficiency, average deposited energy per interacting x-ray, Swank noise factor, and detective quantum efficiency are tabulated by means of graphs which may help with the design and selection of materials for photoconductor-based mammography detectors. Neglecting the electrical characteristics of photoconductor materials and taking into account only x-ray interactions, it is concluded that PbO shows the strongest signal-to-noise ratio performance of the materials investigated in this study.},
doi = {10.1118/1.3702455},
url = {https://www.osti.gov/biblio/22098841}, journal = {Medical Physics},
issn = {0094-2405},
number = 5,
volume = 39,
place = {United States},
year = {2012},
month = {5}
}