PRISM SHEET AND SURFACE ILLUMINATION DEVICE FORMED BY USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a prism sheet capable of sufficiently suppressing the occurrence of Newt on rings, obscuring flaws and maintaining well the effect of condensing incident light in a front surface direction. SOLUTION: A prism array forming layer 14 is attached to the front surface side of a base body layer 12 and a light diffusion layer formed by supporting many glass beads 16 sized 5 to 50μm in diameter by a supporting layer 18 is attached to the rear surface side thereof. The front surfaces of the prism array forming layer 14 are formed as prism arrays arranged with plural isosceles triangle unit prisms 14a of 90 deg. in vertex angle θ.