LINEAR FRESNEL LENS SHEET AND ROLL-STATE MOLD FOR MANUFACTURING LINEAR FRESNEL LENS SHEET

摘要

PROBLEM TO BE SOLVED: To provide a linear fresnel lens sheet capable of improving brightness difference between a vicinity of a center area and other areas to an inconceivable level in the linear fresnel lens sheet, the difference capable of occurring depending on an observation position of an observer.;SOLUTION: A linear fresnel lens sheet 1 includes: a first lens surface group 10 including a plurality of first lens surfaces 11 with lens surfaces thereof aligned in one direction and inclined to the same side with regard to a normal direction N; a second lens surface group 20 including a plurality of second lens surfaces 21 inclined to a side opposite to the first lens surfaces 11 with regard to the normal direction N; and a flat part 30 arranged between the first lens surface group 10 and the second lens surface group 20 in the one direction. The flat part 30 includes one or more flat surfaces 31 extending along a sheet surface 1a of the linear fresnel lens sheet 1.;SELECTED DRAWING: Figure 1;COPYRIGHT: (C)2017,JPO&INPIT