New IQI for digital radiography

Radiographic Test (RT) has been widely used in industries to detect inner defects of welded structures or any other significant components. Especially in the nuclear industry, film radiography is the dominant and standardized procedure in performing radiographic testing. Lately emphasis is on digital radiography. One of the most serious concerns for digitization is the lack of image resolution standardizing device like resolution gauge which would determine imaging parameters such as modular transfer function (MTF). This paper proposes line pair type image quality indicator (IQI) corresponding to the current IQIs for both hole and wire type. The advantage of this IQI is to enable easier calibration of testing conditions and quantification of digital RT image quality with required MTF that should be clearly defined in the examination procedures. Furthermore, to acquire "resolution-ensured" digital image of existing RT films, we developed line pair type standardization film. Prototypes of line pair type IQI and line pair type standardization film are currently in the validation study and trial implementing process. These results are also reported in this paper.