a plurality of lighting units each of which comprises a light conductor plate having a light-conductor surface as a light outlet surface, the light-conductor surface emitting light from a top surface of the light-conductor surface, and a side surface as a light inlet surface, and a light source disposed at the light inlet surface of the light conductor plate, and which are arranged two dimensionally; and

a plurality of light transmissive members each of which is provided with means to reflect and diffuse light from the light source, and each of which is disposed at a light outlet surface side of each of the lighting units, wherein each of the plurality of light transmissive members emit light from a top surface of each of the light transmissive members,

wherein the plurality of lighting units are arranged such that a predetermined distance is provided between respective opposing ends of the light conductor plates of at least two lighting units adjacent to each other with respect to a direction orthogonal to the light inlet surface of the light conductor plate, and

wherein the light transmissive members bridge the respective opposing ends of the light conductor plates of the at least two adjacent lighting units such that an end region of one of the light transmissive members attaches respective opposing end regions at the top surface of the light conductor plates of the at least two adjacent lighting units so as to directly cover the light source.