| 摘要 |
PURPOSE: To provide a thin surface light source element capable of simply obtaining convergent light in the direction to which a user views as the rear lighting of a display device with a small view angle. CONSTITUTION: This element is constituted of a first element 50 making a side end 11 an incident plane, and making the plane orthogonally intersecting with the incident plane a light emission plane, a reflection plane 13, a second element 51 provided with the incident plane of the outgoing light from the first element 50 and the light emission plane 32 emitting the light having many prism units 40 formed in parallel to the incident plane of the first element 50 on the surface and a light source 14. The outgoing light having directivity in the specified direction having inclination for the normal direction of the light emission plane 16 in the plane direction orthogonally intersecting with both of the light emission plane 16 and the incident plane of the first element 50 is emitted from the light emission surface 16 of the first element 50, and the outgoing light from the first element 50 is deflected in the normal direction by the second element 51. |
