A light device includes a light guide member having first, second and third portions. An array of light-modifying elements are formed on one main surface of the light guide member, and each light-modifying element having surfaces inclined with respect to at least one of the main surfaces of the light guide member. The light-modifying elements are configured to diffuse incident light. A light source (or light sources) is provided on a substrate, and configured to project light along a thickness direction of the light guide member. The first and third portions of the light guide member are provided at different distances from the substrate, with the second portion being inclined to an acute angle with respect to the substrate.