A backlight arrangement (100) comprising at least a light source (101) and a waveguide plate (102) comprising a front surface (104) and an opposing back surface (103) and at least one surface (107) for receiving light from said light source (101), said surface for receiving light connecting said front and back surfaces is provided. At least one of said front surface (104) and said back surface (103) is a facetted surface comprising a plurality of planar parallel portions (105) and a plurality of facets (106) connecting said planar parallel portions. The facets (106) are formed such that the thickness of said waveguide plate (102) decreases stepwise with the distance from said surface (107) for receiving light, and such that at least part of the light received into the waveguide plate (102) via said surface (107) for receiving light is extracted from said waveguide plate (102) through said facets (106).