| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a direct backlight device reduced in consumption power and suppressing a variation in brightness of a light emitting surface. <P>SOLUTION: The backlight device includes a plurality of almost parallel-disposed linear light sources A, B and a light diffusion plate 30. AX is a position where the center AC of an arbitrary linear light source A is projected to the light diffusion plate 30, CY is a position where an intermediate position C between the linear light source A and the adjacent linear light source B is projected to the light diffusion plate 30, R(mm) is an outer diameter of each of the linear light sources A, B, D1(mm) is a distance between the outer periphery of each of the linear light sources A, B and a light incident surface and Z(mm) is a gap between an end in an extending-out direction of a support and an end of the light diffusion plate 30 supported by the support. At least two or more kinds of irregularity structure groups 100, 200 of pluralities of irregularity structures are formed on a light outgoing surface or the light incident surface between the positions AX and CY. A boundary 150 between the adjacent irregularity structure groups 100, 200 is at a position apart from the position AX by a distance exceeding R/2+Z+Z/(1+D1)(mm). <P>COPYRIGHT: (C)2009,JPO&INPIT |
