LIGHT CONDENSABLE DIFFUSION PLATE, AND ILLUMINATION PANEL FOR BACK LIGHT USING THE SAME

PROBLEM TO BE SOLVED: To make printed dot patterns invisible, front surface luminance high and practicable strength sufficient, and prevent the change with time by providing a diffusion plate which has a light condensable structure in which triangular-shaped columnar bodies are arranged in the section, and has a light diffusive structure contg. air for adhering hollow beads on the surface on the side opposite thereto. SOLUTION: This diffusion plate is formed to a prism form arranging columnar bodies 2 of a triangular shape in the section like straight ridges on one surface of a sheet 1. The triangular shape in the section is not particularly restricted and may be an isosceles or scalene shapes. The vertex of the triangular shapes is preferably 80 to 120 deg.C. The rounded vertex is equally well. The light diffusive structure 7 contg. the air is obtd. by adhering the hollow beads and/or solid beads 5 onto an ordinary flat planar sheet 4 separated from the sheet 1 having the light condensable structure 3 by using a resin 9 for coating, by which the light diffusive structure sheet 6 is obtd. The projection parts of the beads 5 are formed by adhering the projecting parts to the opposite flank of the sheet 1 having the light condensable structure 3 by using the adhesive 8.