| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical control plate capable of more stably suppressing the unevenness of brightness, a surface light source device, and a transmissive image display device. <P>SOLUTION: A light diffusing plate (optical control plate ) 40 allows light impinging from a first surface 40a to be emitted from ad second surface 40b. A plurality of projections 41 extended in a first direction and disposed in parallel in a second direction perpendicular to the first direction are formed on the second surface. When, in cross sections orthogonal to the first direction of the projections, an axis passing both ends in the second direction of the projections is denoted as an x axis and an axis passing centers of both ends on the x axis and being orthogonal to the x axis is denoted as a z axis, a contour shape z(x) of the projections the in cross sections satisfies 0.95×z<SB>0</SB>(x)≤z(x)≤1.05×z<SB>0</SB>(x) wherein z<SB>0</SB>(x) is expressed by formula (2). In the formula (2), w<SB>a</SB>represents a length in the x-axis direction of projections and h<SB>a</SB>=0.525w<SB>a</SB>and k<SB>a</SB>=-0.4. <P>COPYRIGHT: (C)2011,JPO&INPIT |
