Lenticular lens sheet and projection screen

摘要

A high contrast a lenticular lens sheet that improves the brightness of an image and the angle of visibility. The width A, between the lens elements on a light-emission side and a side wall of a black stripe portion is made to be 15 mum or less. P represents the pitch of the lens element and H represents the width of the black stripe portion as viewed n a cross section perpendicular to the lens element, the difference F in height between the black stripe portion and the lens element is set to have a range that is expressed by the inequality: 0.098 P<=F<=(P-H)/2 tan(pi/3). Simultaneously, the width B as measured from an apex portion of the black stripe portion in regard to a colored portion on a side wall of the black stripe portion is set to have a range that is expressed by the inequality: 0.30 F<=B<=0.89 F.