| 摘要 |
PROBLEM TO BE SOLVED: To obtain an improved thin deformative film in which incident light beams in a specified angle range cause inward total reflection by constituting the film in such a manner that the faces which make a right angle of each prism show a specified angle to the smooth surface opposite to a structural face of the film. SOLUTION: This thin deformative film 10 has a structural face 12 on one side and a smooth face 14 on the opposite side to the structural face 12 and consists of a transparent polymer material. The structural face 12 is produced by arranging small prisms each having an almost isosceles cross section with a right angle parallel to each other to form plural projections 17 and grooves 18 stretching in the longitudinal direction of the film 10. When the film 10 is flat, the face 20 which forms the right angle makes about 45 angle from the smooth face 14 adjacent to the face 20. Further, when the film 10 is bent to form a continuous radial curved line of the smooth face 14, the angle of the face 20 changes from 45 and the face 20 is bent. However, these state do not give any significant influences on the performance of the film 10. |
