| 摘要 |
The entrance region of this light flux control member has second protruding strips disposed at the edges of a virtual quadrangle, and angle parts disposed at the four corners of the virtual quadrangle. The angle parts are approximately pyramidal parts having a third entrance face, and a third reflective face establishing a connection between two neighboring second reflective faces. The height of a third crest line at the boundary between the third entrance face and the third reflective face decreases gradually as a diagonal line of the virtual quadrangle is approached. In addition, the distance between the outermost edge of the third reflective face and the third crest line decreases gradually as the diagonal line of the virtual quadrangle is approached. In addition, the distance between the extremities of a second crest line of the second protruding strip is shorter than the distance between the extremities of a first crest line located most outward. |
