| 摘要 |
PURPOSE:To obtain a projection screen which eliminates a valley of a distribution of the light quantity by adding a diffusion sheet to a lenticular screen which has a total reflecting surface. CONSTITUTION:The lenticular screen 1 has total reflection parts 3 at base parts of convex refracting surfaces 2 and provides such a distribution of the quantity of light that totally reflected light from total reflecting surface parts 3 is large at a large angle of diffusion. The diffusing flat plate 4 formed by adding a diffusing agent is added in the optical path after the diffusion of the screen 1, i.e. to an observation side. The screen 1 is made of acrylic resin, etc., and the lenticular lens with a 3mm. thickness (t) and the total reflecting surfaces 3 has a 0.5mm. width P1, 0.25mm. width P3 and 0.18mm. radius r1 of curvature of the lens surfaces, 0.7mm. width P2 and 0.4mm. radius r2 of curvature of lens surfaces, and 75 deg. angle Q of the total reflecting surfaces to the screen surface. The plate 4 is formed by adding 23g/m<2> silicon oxide fines as the diffusing agent to acrylic resin, etc. |
