| 摘要 |
PROBLEM TO BE SOLVED: To avoid a defect in display uniformity due to the roundness of corner parts of an optical wave guide body by providing the optical wave guide body with at least one expanded part integrally formed on its light entering side. SOLUTION: An expanded part 35 is formed by extending a small-width side 34 of an optical wave guiding body 33, and the small-width side 34 forms one side face of the expanded part 35 and has an end 41 shifting to a round part 42. The side face 43 limits the expanded part 35 and thereby, the expanded part 35 is formed into a wedge-like shape. A broken line 44 forms an angle of 50 deg. with respect to the small-width side 34, a broken line 45 forms an angle of 90 deg. with respect to the small-width side 34, and the expanded part 35 is so molded that the side face 43 intersects with all light-rays positioned between the broken lines 44, 45 originating from the end 41. Thereby, all defects which are generated based on the round part 42 and propagate in the optical wave guiding body 33 are retained in the region of the expanded part 35. Therefore, an observer who sees only a display region can not see the defects. |
