Triangular-pyramidal cube-corner retroreflection sheet
US6390629B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 23, 2000 |
| Grant date | May 21, 2002 |
| Priority date | — |
| Expiry date | Oct 23, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/124
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A triangular-pyramidal cube-corner retroreflective sheeting characterized in that a lateral face (prism face) (face c) using a base edge (x) of triangular-pyramidal reflective elements faced each other and arranged in the closest-packed state by sharing the base edge (x) on a base plane (X-X′) as one side is hexagonal or triangular, two other faces (faces a and b) sharing one ridge line starting with an apex (H) of the triangular-pyramidal reflective elements is quadrangular and when assuming the height from the apex (H) up to the base plane (X-X′) as (h) and the height up to a substantially horizontal plane (Z-Z′) including base edges (z and w) of other two faces (faces a and b) as (h0), and the angle formed between the optical axis of the triangular-pyramidal reflective elements and a plane (Y-Y′) including the base edge (x) and vertical to the base plane (X-X′) as (&thgr;), h and h0 are not substantially equal to each other but h/h0 and &thgr; meet a specific relational expression.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.