Patent ID: 7946746

Claim:
A surface light source device comprising: at least four light guide plates each being rectangular in shape and comprising a light emitting face, a bottom face opposite to the light emitting face, and four side faces interconnecting the light emitting face and the bottom face, the four side faces of each light guide plate comprising at least two mounting faces and at least a splicing face, the at least four light guide plates being spliced together by the at least a splicing face of one of the at least four light guiding plates being closely adjacent to one of the at least two mounting faces of a neighboring one of the at least four light guiding plates, at least two neighboring ones of the four side faces of each light guide plate each being closely adjacent to a corresponding side face of one of two neighboring guiding plates of the each light guide plate; and a plurality of LEDs attached in each of the at least two mounting faces of each of the at least four light guide plates, the LEDs in each of the at least two mounting faces being arranged in a line, the at least a splicing face being without any LED therein.