Seamless integration of illumination into interior trim panels with decorative surface materials

A decorative cover for a back-illuminated interior trim panel for a vehicle, said cover being a sturdy shell-structure comprising a transparent plate, forming the back side of the shell-structure, and a decorative component top layer comprising a trim material layer, which forms the outer surface of the decorative cover, wherein the trim material layer is formed from a trim material which is one from a group of materials consisting of a wood veneer, a paper, a textile and a fabric, wherein the decorative component top layer is configured to have a predetermined degree of translucency, and wherein the sturdy shell-structure is formed by back-injecting against the decorative component top layer, such that the sturdy shell-structure is a seamless, single component structure and wherein the decorative component top layer is non-permeable to the back-injected material.