| 摘要 |
A set of light guide blocks B L 1 SIMILAR B L 3 provide a tandem arrangement. The light guide block B L 1 is supplied with light from a primary light source L 1. The other primary light sources L 2, L 3 are arranged in recesses formed around distal portions of the light guide blocks B L 1, B L 2, supplying the light guide blocks B L 2, B L 3 with primary light, respectively. Overlap of mutually neighbouring light guide blocks gives tang-shaped overlapping portions 17a, 17b, 27a, 27b as well as overlapping bands 17c, 27c, thereby avoiding electrodes at both ends of the primary light sources L 2, L 3 from causing short of brightness. The light guide blocks B L 1 SIMILAR B L 3 may be in the form of unified single guide plate. Primary light sources L 1 SIMILAR L 3 may have a shape such that electrode sections of both ends are curved. A compact surface light source device with a large emission area is provided. <IMAGE> |
