A scatter correction using thickness iteration in dual-energy radiography

With area detectors, scattered radiation causes the dominant error in separation of different materials properly. Several methods for the scatter correction in dual energy imaging had been suggested and improved results. Such methods, however, need additional lead blocks or detectors, and additional exposures to estimate the scatter fraction for every correction. We suggest the scatter correction by using a database of the fraction and distribution of scattered radiations. To verify this method we did MCNP simulation. The generation of the scatter information for each combination of thickness of an aluminum-water phantom had been done. Based on the uncorrected signals, thickness of each material can be calculated by a conventional dual-energy algorithm. And then the scatter information of corresponding thickness from the look-up table is used to correct the original signals. The iterative scatter correction reduced relative-thickness error in results. This scatter correction method can be applied to two-material dual-energy radiography like mammography, contrast imaging, or industrial inspection.