| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a light converging sheet capable of performing even and uniform illumination irrespective of the position for observing a screen, to provide a surface illuminant device, and to provide a transmission type display device provided with the surface light source device. <P>SOLUTION: The light converging sheet is formed by arranging a large number of unit lenses 141 side by side on the emission side, wherein a scattering layer 142 for scattering light is formed along the surface convex shape of the unit lens 141. The thickness t of the scattering layer 142 is made to be at least 1/10 of lens pitch p. Further, the light converging sheet satisfies the following relation, d((t+h+p)/ϕ)>50% and d(t/ϕ)<50%, wherein d (%) is a volume ratio of light diffusing particles mixed in the scattering layer 142 and ϕ(mm) is an average particle size of light diffusing particles. Thereby, while enhancing the probability that the light emitted at a large emission angle is scattered, the light emitted at a small emission angle is emitted without being scattered so much and, therefore, the convergence of light can be more effectively performed. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
