| 摘要 |
<p>Provided is a direct backlight apparatus which has sufficient luminance in a front direction, suppresses luminance nonuniformity on a light emitting surface and reduces power consumption. The direct backlight apparatus is provided with a linear light source (2), a reflecting plate (3) and a light diffusing member (1). A distance (a) between the center of the adjacent linear light sources (2) is 30mm-65mm. The light diffusing member (1) has a substantially flat light entrance surface (1A) and a light outgoing surface (1B) whereupon a plurality of linear prisms (4) are arranged. The linear prism (4) has two inclined surfaces (4A) having substantially the same inclination angles to a surface vertical to the thickness direction of the light diffusing member (1). The relationship of a/7<L<a/4 is satisfied, where, L(mm)is a distance between a center position S of one image of two images on the light outgoing surface for one linear light source and a position R whereupon the center of the one linear light source is projected on the light outgoing surface.</p> |
