Light Collection Enhancement Analysis for Digital X-Ray Detector Using Gd2O2S:Tb and CsI:Tl Phosphors in Nanoscale Treatment - Atomic Nanoscale Technology in the Nuclear Industry - page 67

6
LightCollectionEnhancementAnalysis
forDigitalX-RayDetectorUsing
Gd 2 O 2 S:TbandCsI:TlPhosphors
in Nanoscal eTreatment
TaehoWooandTaewooKim
CONTENTS
6.1. Introduction................................................................................................... 67
6.2. Method........................................................................................................... 69
6.3. Results............................................................................................................ 72
6.4. Conclusions................................................................................................... 73
References............................................................................................................... 74
6.1 Introduction
The.clinical.mammography.examination.involves.light.collection.enhance-
ment.on.the.nanoscale..Breast.cancer.is.highly.ranked.among.cancer.death.
rates.in.American.women..It.is.important.to.detect.cancer.cells.in.the.early.
stages.of.the.disease.so.that.treatment.can.begin.as.soon.as.possible..In.the.
United.States.(International.Agency.for.Research.on.Cancer.2008),.the.ive-
year. survival. rate. for. breast. cancer. is. 85%. when. the. cancer. is. localized. to.
the. breast.. In. other. words,. the. mortality. rate. is. reduced. to. 56%. when. the.
auxiliary. nodes. are. included.. The. classical. screen/ilm. mammography. is.
considered. a. reliable. diagnostic. test. but. masses. and. microcalculations. can.
be.dificult. to.image. in.dense.breasts..Therefore,.direct.digital. x-ray.image.
acquisition.is.necessary.
The. active. matrix. lat-panel. imagers. (AMFPIs). are. being. developed. for.
x-ray. detection. systems.. Wronski. investigated. high-gain. avalanche. rushing.
photodetectors.(HARP).for.avalanche.multiplication.(Wronski.and.Rowlands.
2008).. This. study. showed. that. avalanche. gains. enable. x-ray. quantum. noise.
limited. performance. throughout. the. entire. exposure. range. in. radiography.
and.luoroscopy,.respectively..In.addition,.a.charge-coupled.device.(CCD).is.
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