Patent ID: 6890634

Claim:
A retroreflective article comprising a flat front surface and a structured rear surface, the structured rear surface comprising: a continuous arrangement of three triangles, wherein the three triangles are mutually perpendicular and comprise one common point, three common edges, and three uncommon edges, wherein each common edge is shared by two triangles, and wherein each uncommon edge belongs to only one triangle; and a continuous arrangement of trigonal linear prisms, wherein each trigonal linear prism is disposed along one of the uncommon edges, each trigonal linear prism having a first surface and a second surface which define an apex edge, a first base edge, and a second base edge, wherein the first surface and the second surface of each trigonal linear prism are tilted relative to the flat front surface of the retroreflective article, wherein a polyhedron optical axis extending from the common point to the front surface of the retroreflective article is tilted by −15° to 15° to an axis normal to the front surface of the retroreflective article, wherein angles between the polyhedron optical axis and a surface of each of the three triangles are the same.