| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pipe which has a simple structure and is inexpensive and high in the uniformity of the directional characteristics of light intensity and luminance although the length as element is short; an illumination optical apparatus which has realized cost reduction and miniaturization as the whole apparatus by using the same, is high in the brightness and the uniformity of the brightness over a prescribed area, and can perform an illumination good in the directional characteristic of the luminance; and an optical apparatus using the same. <P>SOLUTION: In the optical pipe having an incident face 5a, an exit face, and a side face reflecting light which is made incident from the side of the central axis 6b passing the center of the incident face 5a and the center of the exit face, at least a part of the side face is formed into a corrugated shape when viewed on the cross section including the central axis 6b. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
