• Journal of Radiation Protection and Research
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• v.35 no.1
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• pp.26-33
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• 2010

A computed Radiography (CR) system by use of reusable Image Plate (IP) offers a convenient and reliable way to replace a conventional film-screen system for NDT (non-destructive testing) field. The quality of a radiography to detect a defect of welded objects depends on the procedure embracing several factors such as measurement conditions, image plate type/class, radiation energy, radiation type, and source to image plate distance. Also, the ability of images to detect a flaw reduces with increasing object thickness. In the study, the properties of gamma ray source were summarized for NDT field and inspection images of CR image system manufactured by FUJI were acquired using $^{75}Se$ and $^{192}Ir$ with welded objects. We analyzed the gray scale of hole defect image by using XCAP image processing program and calculated the image contrast and SNR in definition. Also the sesitivities of image quality indicator(IQI) were calculated for hot and cooling tube image of $^{75}Se$ and $^{192}Ir$.

• Journal of the Korean Society of Radiology
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• v.4 no.4
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• pp.37-40
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• 2010

In this paper, transport properties of charge carrier which is produced by x-ray exposure were investigated.. It is the research of charge transport and specific property of trap that is performed in direct digital x-ray image receptor. We measured transit time and drift mobility of charge carriers of a-Se photoconductor using time-of-flight method. We made a testing glass with a-Se of $100{\mu}m$ thickness on corning glass using thermal evaporation method. As a result of this experiment, electron and hole transit time was each $229.17{\mu}s$ and $8.73{\mu}s$ at $10V/{\mu}m$ electric field and drift mobility was each $0.00174cm^2/V{\cdot}s$, $0.04584cm^2/V{\cdot}s$. But the results shows us different measurement value of electron and charge drift mobility and it was investigated about charge transport properties and trap mechanism.