Abstract <p>An indirect-drive cryogenic target is a hollow spherical shell-capsule with a solid layer of hydrogen isotopes (fuel) on its inner surface, located in a box-converter, which in turn is mounted in a cryostat to provide for operation at a cryogenic temperature. Before placing a target in an ignition experiment at a megajoule energy level facility, a thorough characterization of all component elements of the target and of the finished target must be completed. This paper describes three-dimensional modelling of a visible radiation beam propagation through a cryogenic target to study the robustness of optical shadow method for characterization of a solid fuel layer in an optically transparent shell in the presence of harmonic perturbations of various orders and amplitudes of the shell and fuel layer surfaces, as well as under nonideal experimental conditions.</p>