Patent ID: 8752994

Claim:
Illumination system comprising: a light source for emitting light with a basic emission distribution around a symmetry axis, and a collimator for redirecting light from the light source to substantially homogeneously illuminate at least a part of an illuminating surface, at least a part of the homogeneously illuminated illuminating surface extending substantially parallel to the symmetry axis, the collimator comprising a concave input window for receiving light from the light source, and further comprising an at least partially convex output window for directing light towards the illuminating surface, a convex part of the output window being shaped for refracting light emitted by the light source in a direction away from the illuminating surface back towards the illuminating surface and for generating an altered emission distribution being asymmetric with respect to the symmetry axis of the basic emission distribution to substantially homogeneously illuminate the at least part of the illuminating surface, wherein the collimator comprises an edge-wall arranged between the input window and the output window, in between the input window and a boundary edge the edge-wall being arranged substantially symmetric around a further symmetry axis, and comprising a substantially parabolic shape in a cross-section through the further symmetry axis, wherein the further symmetry axis of the collimator and the symmetry axis of the emission distribution intersect substantially at a focal point of the concave input window, and wherein the further symmetry axis is tilted with respect to the symmetry axis of the emission distribution over a tilting angle.