An illumination system, preferably for illumination in a car, comprising at least one plain or slightly curved, solid light guide (4) made of transparent material, said light guide receiving light from a light (2) source and being provided with means (5, 6) for extracting light from said light guide, the means for extracting light from said light guide have. Reflecting surfaces (7, 8, 9, 10) the slopes of which are varied as a function of the position of the extracting means in the light guide as well as the position of a reading plane, so as to direct the light flux to a desired reading plane position. Preferably the illumination system a laminated structure of light guide layers, said layers being formed of a light guide layer for diffuse homogeneous illumination (1) and at least one light guide layer (4) for spot illumination of a reading plane.