scholarly journals Radiation Imaging with Caesium Bromide Storage Phosphors

2021 ◽  
Author(s):  
◽  
Nicola Maree Winch
Keyword(s):  
Conversion Efficiency ◽  
Dual Energy ◽  
Neutron Imaging ◽  
Imaging Plate ◽  
Storage Phosphor ◽  
X Ray ◽  
Imaging Results ◽  
Dual Energy Imaging ◽  
Storage Phosphors ◽  
Imaging Plates

<p>This thesis is centred on the development of a new method to prepare semitransparent CsBr:Eu²⁺ imaging plates for high resolution X-ray radiography. Methods of characterising the performance of these plates, and their application to dual energy imaging and neutron imaging are discussed. The basic preparation method, based on high-pressure uniaxial compression of powder mixtures of CsBr and EuBr₂, produces imaging plates which show good transparency and resolution. These imaging plates have a conversion efficiency of 1.5 pJmR⁻¹mm⁻³ compared to 5.1 pJmR⁻¹mm⁻³ for a commercial needle imaging plate. Water is found to play a critical role in the photostimulated luminescence activation in CsBr:Eu²⁺ storage phosphors, and imaging plates subsequently hydrated at room temperature have an increased conversion efficiency of up to 11 pJmR⁻¹mm⁻³, better than the commercial material. A model has been suggested for the generation of the PSL active site in the imaging plates based on thermomechanical sintering and water-induced crystal regrowth. A precise method for determining the conversion efficiency and stimulation energy of X-ray storage phosphor materials using an integrating sphere has been developed and used to characterise the materials developed in this thesis. A novel read-out method for storage phosphor imaging plates based on flood illumination and a semi-professional digital camera has also been developed and tested. Good quality X-ray images are obtained and the method shows excellent promise as a low-cost, portable X-ray imaging system. A stratified detector using CsBr imaging plates has been developed for use in dual-energy imaging. Results suggest that it is possible to perform dual-energy imaging with this structure. CsBr:Eu²⁺ imaging plates have been produced with added neutron converters for use as thermal neutron imaging plates. An imaging plate with 5 % ¹ºB₂O₃ added as a neutron converter has a PSL output 50 % that of a commercial neutron imaging plate. Neutron imaging with these imaging plates has been successfully demonstrated.</p>

scholarly journals Radiation Imaging with Caesium Bromide Storage Phosphors

2021 ◽  
Author(s):  
◽  
Nicola Maree Winch
Keyword(s):  
Conversion Efficiency ◽  
Dual Energy ◽  
Neutron Imaging ◽  
Imaging Plate ◽  
Storage Phosphor ◽  
X Ray ◽  
Imaging Results ◽  
Dual Energy Imaging ◽  
Storage Phosphors ◽  
Imaging Plates

<p>This thesis is centred on the development of a new method to prepare semitransparent CsBr:Eu²⁺ imaging plates for high resolution X-ray radiography. Methods of characterising the performance of these plates, and their application to dual energy imaging and neutron imaging are discussed. The basic preparation method, based on high-pressure uniaxial compression of powder mixtures of CsBr and EuBr₂, produces imaging plates which show good transparency and resolution. These imaging plates have a conversion efficiency of 1.5 pJmR⁻¹mm⁻³ compared to 5.1 pJmR⁻¹mm⁻³ for a commercial needle imaging plate. Water is found to play a critical role in the photostimulated luminescence activation in CsBr:Eu²⁺ storage phosphors, and imaging plates subsequently hydrated at room temperature have an increased conversion efficiency of up to 11 pJmR⁻¹mm⁻³, better than the commercial material. A model has been suggested for the generation of the PSL active site in the imaging plates based on thermomechanical sintering and water-induced crystal regrowth. A precise method for determining the conversion efficiency and stimulation energy of X-ray storage phosphor materials using an integrating sphere has been developed and used to characterise the materials developed in this thesis. A novel read-out method for storage phosphor imaging plates based on flood illumination and a semi-professional digital camera has also been developed and tested. Good quality X-ray images are obtained and the method shows excellent promise as a low-cost, portable X-ray imaging system. A stratified detector using CsBr imaging plates has been developed for use in dual-energy imaging. Results suggest that it is possible to perform dual-energy imaging with this structure. CsBr:Eu²⁺ imaging plates have been produced with added neutron converters for use as thermal neutron imaging plates. An imaging plate with 5 % ¹ºB₂O₃ added as a neutron converter has a PSL output 50 % that of a commercial neutron imaging plate. Neutron imaging with these imaging plates has been successfully demonstrated.</p>

scholarly journals A Method to Improve Electron Density Measurement of Cone-Beam CT Using Dual Energy Technique

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Kuo Men ◽  
Jian-Rong Dai ◽  
Ming-Hui Li ◽  
Xin-Yuan Chen ◽  
Ke Zhang ◽  
...  
Keyword(s):  
Electron Density ◽  
Cone Beam Ct ◽  
Density Measurement ◽  
Dual Energy ◽  
Cone Beam ◽  
Imaging Method ◽  
Basis Material ◽  
X Ray ◽  
Dual Energy Imaging ◽  
Set Up

Purpose. To develop a dual energy imaging method to improve the accuracy of electron density measurement with a cone-beam CT (CBCT) device.Materials and Methods. The imaging system is the XVI CBCT system on Elekta Synergy linac. Projection data were acquired with the high and low energy X-ray, respectively, to set up a basis material decomposition model. Virtual phantom simulation and phantoms experiments were carried out for quantitative evaluation of the method. Phantoms were also scanned twice with the high and low energy X-ray, respectively. The data were decomposed into projections of the two basis material coefficients according to the model set up earlier. The two sets of decomposed projections were used to reconstruct CBCT images of the basis material coefficients. Then, the images of electron densities were calculated with these CBCT images.Results. The difference between the calculated and theoretical values was within 2% and the correlation coefficient of them was about 1.0. The dual energy imaging method obtained more accurate electron density values and reduced the beam hardening artifacts obviously.Conclusion. A novel dual energy CBCT imaging method to calculate the electron densities was developed. It can acquire more accurate values and provide a platform potentially for dose calculation.

scholarly journals Use of Imaging Plates in X-Ray Analysis

1997 ◽  
Vol 29 (1-2) ◽  
pp. 89-101 ◽  
Author(s):  
M. Ermrich ◽  
F. Hahn ◽  
E. R. Wölfel
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Powder Diffraction ◽  
Polycrystalline Materials ◽  
Imaging Plate ◽  
Two Dimensional ◽  
X Ray ◽  
Working Principle ◽  
Imaging Plates

Two-dimensional detectors have opened a new area for the investigation of both single crystals and polycrystalline materials. The working principle of Imaging Plates is described. Some characteristics and the advantages of an Imaging Plate are discussed using the STOE Imaging Plate Diffraction System for different kinds of X-ray analysis: (i) single crystal diffractometry, (ii) powder diffraction and (iii) stress and texture investigations.

scholarly journals Performance assessment of imaging plates for the JHR transfer Neutron Imaging System

2018 ◽  
Vol 170 ◽  
pp. 04021
Author(s):  
E. Simon ◽  
P. Guimbal
Keyword(s):  
Performance Assessment ◽  
Dynamic Range ◽  
Imaging System ◽  
Computed Radiography ◽  
High Sensitivity ◽  
High Dynamic Range ◽  
Neutron Imaging ◽  
Imaging Plate ◽  
Intimate Contact ◽  
Imaging Plates

The underwater Neutron Imaging System to be installed in the Jules Horowitz Reactor (JHR-NIS) is based on a transfer method using a neutron activated beta-emitter like Dysprosium. The information stored in the converter is to be offline transferred on a specific imaging system, still to be defined. Solutions are currently under investigation for the JHR-NIS in order to anticipate the disappearance of radiographic films commonly used in these applications. We report here the performance assessment of Computed Radiography imagers (Imaging Plates) performed at LLB/Orphée (CEA Saclay). Several imaging plate types are studied, in one hand in the configuration involving an intimate contact with an activated dysprosium foil converter: Fuji BAS-TR, Fuji UR-1 and Carestream Flex XL Blue imaging plates, and in the other hand by using a prototypal imaging plate doped with dysprosium and thus not needing any contact with a separate converter foil. The results for these imaging plates are compared with those obtained with gadolinium doped imaging plate used in direct neutron imaging (Fuji BAS-ND). The detection performances of the different imagers are compared regarding resolution and noise. The many advantages of using imaging plates over radiographic films (high sensitivity, linear response, high dynamic range) could palliate its lower intrinsic resolution.

An imaging-plate detector for small-angle neutron scattering

2000 ◽  
Vol 33 (5) ◽  
pp. 1253-1261 ◽  
Author(s):  
Y. T. Cheng ◽  
D. F. R. Mildner ◽  
H. H. Chen-Mayer ◽  
V. A. Sharov ◽  
C. J. Glinka
Keyword(s):  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Imaging Techniques ◽  
Neutron Imaging ◽  
Small Samples ◽  
Imaging Plate ◽  
Position Sensitive ◽  
Transfer Method ◽  
Imaging Plates

Small-angle neutron scattering (SANS) measurements have been performed on long-flight-path pinhole-collimation SANS instruments using, as a two-dimensional position-sensitive detector, both a neutron imaging plate, incorporating gadolinium, and a two-step transfer method, with dysprosium foil as the image transfer medium. The measurements are compared with corresponding data taken using conventional position-sensitive gas proportional counters on the SANS instruments in order to assess the viability of the imaging techniques. The imaging plates have pixel sizes of about two orders of magnitude smaller than those of the gas proportional counter. The reduced pixel size provides definite advantages over the gas counter in certain specific situations, namely when limited space necessitates a short sample-to-detector distance, when only small samples (comparable in size to the detector pixels) are available, or when used in conjunction with focusing beam optics.

Effects of x-ray scatter in quantitative dual-energy imaging using dual-layer flat panel detectors

2021 ◽  
Author(s):  
Chumin Zhao ◽  
Stephen Z. Liu ◽  
Wenying Wang ◽  
Magdalena Herbst ◽  
Thomas Weber ◽  
...  
Keyword(s):  
Dual Energy ◽  
Flat Panel ◽  
X Ray ◽  
Flat Panel Detectors ◽  
Dual Energy Imaging

Evaluation of a dichromatic X-ray source for dual-energy imaging in mammography

2002 ◽  
Vol 489 (1-3) ◽  
pp. 509-518 ◽  
Author(s):  
A Tuffanelli ◽  
S Fabbri ◽  
A Sarnelli ◽  
A Taibi ◽  
M Gambaccini
Keyword(s):  
Dual Energy ◽  
X Ray ◽  
Dual Energy Imaging
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