| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem in which a conventional retroreflection sheet can not exhibit retroreflectivity for only incident light incident from a specific direction, such as solar light arriving from a cosmic space. <P>SOLUTION: A retroreflector comprises: a fluid layer which can flow in and out fluid; a condensing lens array arranged along a plane; and a spherical reflecting mirror array comprising spherical reflecting mirrors each of which has a center at the position which is different from the curvature center of a lens surface of a condensing lens, corresponding to each condensing lens of the condensing lens array. Incident light incident from the specific direction along an optical axis of the corresponding condensing lens and the spherical reflecting mirror is retroreflected to a specific direction by being transmitted through the fluid layer and the condensing lens array and reflected at the spherical reflecting mirror array, when the fluid layer is filled with fluid or the fluid is taken out from the fluid layer. <P>COPYRIGHT: (C)2012,JPO&INPIT |
