Patent ID: 7311431

Claim:
A light-emitting apparatus, comprising: a plurality of adjacent, overlapping light-guide plates formed of light-transmissive material, wherein each of the light-guide plates has i) first and second ends, ii) one or more light-emitting surfaces, and iii) one or more reflective surfaces to redirect light within the light-guide plate; wherein, where first and second light-guide plates are adjacent, the first end of the first light-guide plate A) underhangs the second end of the second light-guide plate, and B) is positioned opposite a primary light-emitting side of the apparatus; a plurality of light sources, optically coupled to the first ends of the light-guide plates to illuminate the interiors of the light-guide plates; and a substantially rigid and thermally conductive substrate on which the light-guide plates are assembled, the substrate comprising, for each of the light-guide plates, an elongate planar member which comprises a primary end and a secondary end, the planar member extending in a first direction from the primary end to the secondary end, the primary end comprising a stepped member which comprises: a first planar section that extends upwardly from the elongate planar member, the first planar section comprising an upper end and a lower end; and a second planar section at the upper end of the first planar section, the second planar section extending rearwardly from the first planar section in a second direction which is opposite from the first direction.