| 摘要 |
PURPOSE:To improve the directional pattern of a scattered light, by forming a screen surface with unit specular faces arranged regularly and specifying the shape of this specular face. CONSTITUTION:A screen surface is formed with many unit specular faces 1 arranged regularly; and inrespect to specular faces 1, a reflective film 3 consisting of Al or the like is stuck to the spherical curved faces formed with concaves and convexes on the surface of a base material 2, and the reflective film 3 is coated with a protecting film 4. The specular face 1 is a spherical curved face having the same curvature practically in the lateral direction and the longitudinal direction of the screen, and a length of the chord of the curved face is 10mu<S<600mu, and the relations of 6<Sx/dx<23 and 18<Sy/dy<92 are satisfied when lengths of chords in the lateral direction and the longitudinal direction are denoted as Sx and Sy and differences in height of the spherical curved face in these two directions are denoted as dx and dy respectively. |
