| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent flexure of a light correction sheet in a planar lighting system with a simple form as compared with a conventional one. <P>SOLUTION: Engagement projections 4a each having a rectangular engagement cross section and rectangular engagement holes 2a each having a size including the rectangles thereof are formed on a right and left sides of a rectangular casing 4 and on the side of the upper side thereof in a symmetrical form at symmetrical positions by using a longitudinal center axis of the casing 4 as a symmetrical axis. The major axes of the rectangles of the engagement cross sections of the right and left engagement projections 4a are set downward-sloping and upward-sloping, respectively and the major axes of the engagement holes 2a are set parallel with the major axes of the rectangles of the engagement cross sections. In the state where the engagement holes 2a are engaged with the engagement projections 4a, the upper left-side downward oblique side of the left engagement hole 2a is brought into tight contact with the upper left-side downward slop of the left engagement projection 4a, the engagement hole 2a contacts the engagement projection 4a only at the oblique side, and other parts thereof are brought in a positional relationship without contacting one another. The right elements are similarly arranged. <P>COPYRIGHT: (C)2007,JPO&INPIT |
