High efficiency cube corner retroflective material
US4938563A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 1988 |
| Grant date | Jul 3, 1990 |
| Priority date | — |
| Expiry date | May 20, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides a retroreflective material which is efficient at high angles of incidence and which may be individually tailored so as to distribute light retroreflected by the material into a desired pattern or divergence profile. The retroreflective material of the present invention comprises a transparent surface layer having a front side and a back side and an array of cube corner reflective elements, each of the reflecting elements including a rectangular base on the back side of the surface layer, two rectangular faces nearly perpendicular to each other each one being joined to an edge of the rectangular base to form a reflecting element having a triangular cross section, and two triangular faces that are approximately parallel to each other and approximately perpendicular to the rectangular faces, and forming the ends of the reflecting elements; and the triangular and rectangular faces defining a pair of approximate cube corners therebetween, the reflecting elements arranged with their bases adjacent to the surface layer. The terms "approximately parallel" and "approximately perpendicular" are used herein to refer to faces which are truly parallel or perpendic…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.