DIFFUSING SHEET FOR TRANSPARENT SCREEN AND TRANSPARENT SCREEN

摘要

PROBLEM TO BE SOLVED: To provide a diffusing sheet for a transparent screen with high quality for preventing an observer from having a strange sense even when the observer watches an image on the screen while changing viewing angles. SOLUTION: A plurality of groove paths with an almost V-shaped cross section are provided parallelly on the emitting surface of a main diffusing layer. Each of the groove paths is formed of two plane surfaces, curved surfaces or bent plane surfaces connected inside the main diffusing layer. An area between two adjacent groove paths constitutes a rib with a cross section of an almost trapezoidal shape. The plane surfaces, curved surfaces or bent plane surfaces forming each groove path constitute the side planes of the rib. Light made incident almost vertically on the incidence surface of the main diffusing layer is diffused in the diffusing direction by being reflected at the side planes of the rib. An auxiliary diffusing layer having light diffusing components for diffusing light in the diffusing direction is provided on the emitting surface side of the main diffusing layer or on both the emitting surface side and the incidence surface side. The light diffusing components are adjusted so that the gain curve of emitted light on the diffusing sheet does not have a minimum point. COPYRIGHT: (C)2004,JPO