Radiation detection device, radiation image acquisition device, and radiation image acquisition method

A radiation image acquisition method for detecting x-ray radiation transmitted through a target object conveyed in a conveyance direction using a radiation detection device comprising a first scintillator, a second scintillator, a first line sensor having a plurality of first pixels arranged along a detection direction, a second line sensor having a plurality of second pixels arranged along the detection direction, and an image processing unit, wherein the first pixels and the second pixels are identical to each other in number and are arranged at an identical pixel pitch, the radiation image acquisition method comprising:

• a first conversion step of converting x-ray radiation of a low energy range in the x-ray radiation transmitted through the target object into a first scintillation light by the first scintillator;
• a first detection step of detecting the first scintillation light with the first pixels of the first line sensor to output first image data;
• a second conversion step of converting x-ray radiation of a high energy range in the x-ray radiation transmitted through the target object into a second scintillation light by the second scintillator, the high energy range being higher than the low energy range;
• a second detection step of detecting the second scintillation light with the second pixels of the second line sensor to output second image data;
• a first image processing step of executing a first thinning-out process on the first image data using the image processing unit to output a first converted image, in which the image data of the lower luminance of the signals from adjacent pixels is left, and the remaining image data is removed, the first thinning-out process being a minimum filtering process;
• and
• a second image processing step of executing a second thinning-out process on the second image data using the image processing unit to output a second converted image, in which an average value of luminances of the signals from adjacent pixels is calculated or luminances of signals from adjacent pixels are added together to reduce the quantity of data, the second thinning-out process being an averaging process or an adding process.