| 摘要 |
A backlight device (11) is provided with: a surface light emitting part (15) that outputs light in a surface shape; a light deflecting layer (16) provided on the light output side of the surface light emitting part and to which the light from the light output surface is incident; and a light scattering layer (9) provided on the light output side of the light deflecting layer. The surface light emitting part has: a light guide plate (12); light sources (13) disposed on end surfaces of the light guide plate; and a reflecting plate (14) disposed on the opposite side of the light guide plate from the light deflecting layer. When the brightness at a fixed distance from measuring points on the light output surface for light output from the light output surface for first through fourth azimuth angles which are first, second, third, and fourth azimuth angles within a surface orthogonal to a first direction from the surface light emitting part to the light deflecting layer and for which the angles to a second direction from the light source to the guide plate are 0°, 45°, 90°, and 135°, respectively, is measured in ranges of viewing angles of -40° to +40°, -60° to -74°, and +60° to +74° to the first direction, the brightness for all of the range of viewing angles of -40° to +40° for all of the first through fourth azimuth angles is 40% or less of the maximum value in the brightness for the ranges of viewing angle of -60° to -74° and +60° to +74° for all of the first through fourth azimuth angles. The Hayes value of the light scattering layer is 86% or less. |
