| 摘要 |
PROBLEM TO BE SOLVED: To prevent an invisible state of a screen because of decrease in brightness of the screen depending on the observation direction by specifying the numerical aperture which is determined by the pitch of convex cylindrical lenses, thickness of the lens from the top of the convex of the lens to the opposite flat surface, and width and thickness of a stripe light-shielding pattern formed on the flat surface. SOLUTION: This lenticular sheet which constitutes a transmission type screen in combination with a Fresnel lens sheet has a lens part where convex cylindrical lenses are arranged at a pitch P. The sheet has thickness D from the top of the convex of the cylindrical lens to the flat face opposite to the lens part, and on the flat face, a stripe light-shielding pattern having width P' and thickness D' is formed in the position corresponding to the non-focused part of each cylindrical lens. The numerical aperture defined by (θ-θ')/θis controlled to >90%, whereinθ=tan<-1> (P-P')/2D} andθ'=tan<-1> (P-P')/2(D+D ')}.
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