LIGHT EMITTING DEVICE, SURFACE LIGHT SOURCE DEVICE, DISPLAY DEVICE, AND LIGHT FLUX CONTROL DEVICE

摘要

A display (1) has a member (3) irradiated by a surface light source device (2) comprising a light diffusion member (7) and emission device. The emission device is provided with a light flux control member (5) having a recess (10) and light control emission face (6) which is configurated so as to satisfy Conditions 1 and 2 in a range at least covering a half- intensity- angular- range. Light emitting element(s) (4) may be sealed. Condition 1 is that relation ¸ 5 / ¸ 1 > 1 is satisfied except for light emitted from a light emitting element (4) toward within an angular-neighbourhood of a standard optical axis (L) of the emission device, and Condition 2 is that value of ¸ 5 / ¸ 1 decreases gradually according to increasing of ¸ 1 , where ¸ 1 is an emission angle of any light at being emitted from the light emitting element (4), and ¸ 5 is an emission angle of that light of ¸ 1 at then being emitted from the light control emission face (6) of the light flux control member (5).