This paper shows that it is possible to simultaneously and completely eliminate all third-order monochromatic aberrations, using a component cemented from three plane-parallel plates made from two inhomogeneous materials with a radial refractive-index distribution. It discusses the regions of existence of the solutions that can be physically and technologically implemented. It shows ways of optimizing the refractive-index profiles in order to minimize their falloffs, reduce the level of the residual higher-order aberrations, and broaden the high-quality image field.