Cause of cupping artifacts from radiochromic micelle gel dosimeters used in optical CT scanner measurement

When a radiochromic micelle gel dosimeter is employed for optical computed tomography (CT) measurement, cupping (or dishing) artifacts appear at areas irradiated with a high dose. Anti-scatter polarizer correction is employed to remove scatter signals from optical CT data, but cupping remains. Here, measurement conditions for reducing cupping artifacts are investigated. A change in observation wavelength is found to suppress the cupping influence. Measurements involving aqueous dye solutions with varying jar sizes and dye concentrations reveal cupping artifact behavior under various conditions.