| 摘要 |
PROBLEM TO BE SOLVED: To correct the direction of a transmitted light and to improve the front luminance of a surface light source by forming the surface of a light diffusing layer into a fine rugged face consisting of many streaky ruggednesses oriented practically in a definite direction with a light diffusing film obtained by laminating a light diffusing layer wherein fine particles are dispersed in a transparent resin on one side of a transparent base film. SOLUTION: The light diffusing film 1 is obtained by forming a light diffusing layer 6 consisting of a transparent resin 6a and a fine particle 6b on the surface (light emitting side face) of a base film 7 and forming a fine rugged face 8 consisting of many streaky ruggednesses oriented almost in a definite direction on the surface of the light diffusing layer 6. The fine ruggednesses can be irregularized as well as regularized. The light injected obliquely into the light diffusing layer 6 of the film 1 is diffused by the reflection and refraction on the interface between the fine particle 6b and transparent resin 6a, transmitted through the streaky ruggedness of the fine rugged face 8, refracted as if transmitted through a prism, turned toward the front and emitted. The direction of the transmitted light is corrected in this way, and the light is condensed toward the front. |
