| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a light control plate, with which higher uniformity ratio of luminance can be achieved in a front direction, and to provide a light control plate unit, a surface light source device and a transmission image display device. <P>SOLUTION: The light control plate unit 40 includes first and second light control plates 40<SB>1</SB>and 40<SB>2</SB>sequentially disposed in a plate-thickness direction. The extending direction of first convex parts 43<SB>1</SB>and second convex parts 43<SB>2</SB>, a plurality of which are each formed on upper faces of the respective light control plates, are nearly parallel to each other, a contour shape of the second convex part is a right-angled triangle, and when an axial line passing through both ends of the first convex part in a cross-section surface of the first convex part is used as an x-axis and when an axial line orthogonal to the x-axis is used as a z-axis and when a length of the first convex part in the direction of the x-axis is used as w<SB>a</SB>, the contour shape of the first convex part is represented by z(x) which satisfies 0.95z<SB>0</SB>(x)≤z(x)≤1.05z<SB>0</SB>(x) in -0.475w<SB>a</SB>≤x≤0.475w<SB>a</SB>, wherein z<SB>0</SB>(x) satisfies the following formula: z<SB>0</SB>(x)=(w<SB>a</SB>/2)[summation of C<SB>2k</SB>ä1-(2x/w<SB>a</SB>)<SP>2k</SP>}, k equals from one to eight]. <P>COPYRIGHT: (C)2011,JPO&INPIT |
