Surface Light Source Device

摘要

No other light emission center is included on four edges and within an area surrounded by the four edges of a quadrangle of which light emission centers of four predetermined light sources serve as apexes. A light diffusing member having a first surface that opposes the light sources and a second surface 6 on the side opposite to the first surface is disposed. The light diffusing member emits light emitted from each light source from the second surface in a dispersed state. Projections having a predetermined pyramid shape are formed in an array on the second surface. A virtual bottom surface of the projection positioned on the second surface is configured by a plurality of linear bottom edges. All bottom edges have a positional relationship that is twisted in relation to the four edges and diagonal lines of the quadrangle.