| 摘要 |
PURPOSE:To obtain a bright screen which reduces the generation of moire until it is not discriminated visually and has high resolving power by specifying the width ratio of a Fresnel lens and a lenticular lens within some range and providing a light diffusing means. CONSTITUTION:A back projection screen is formed by forming the Fresnel lens 1 and lenticular lens 2 on a transparent base material which contains a diffusing agent (inorganic material such as SiO2BaSO2 or organic reagent) A, or by providing fine projections and recesses B as the diffusing means B to the surface of the lenticular lens 2 of the transparent base material. In another way, the screen is formed by combining a base material with the Fresnel lens 1 and a base material with the lenticular lens 2 together with a diffusing-agent mixed layer C between. When the width of the Fresnel lens 1 is 1, the width ratio of the lenticular lens is within a range shown by expression I or II (N; 2-12). Thus, moire is eliminated to obtain a superior projection image. |
