Performance evaluate of carbon-interspaced and aluminum-interspaced antiscatter grids based upon the IEC standard fixture

Recently, we have successfully developed very precise carbon-interspaced antiscatter grids by adopting the sawing process used in the semiconductor industry, in order to employ them to digital radiographic (DR) systems. For the systematic performance evaluate, we prepared 12 carbon-interspaced sample grids with strip densities in the range of 40-85 lines/cm for a fixed grid ratio of 5:1 and with grid ratios in the range of 5:1-10:1, in turn, for a fixed strip density of 80 lines/cm and established a well-controlled test condition based upon the IEC standard. For comparison, we also prepared 6 additional aluminum-interspaced sample grids, which were fabricated by using the conventional method, with the same geometrical parameters. In this paper, we presented the performance characteristics of the prepared sample grids with both experimental measurements and calculations in terms of the transmission of primary radiation (T_p), the transmission of scattered radiation (T_s), the transmission of total radiation (T_t), the selectivity (Sigma), the contrast improvement factor (C_if), and the Bucky factor (B). We also described the line artifacts which were easily found in the use of grids in DR imaging systems and proposed possible solutions to overcome these difficulties effectively.