Directly machined raised structure retroreflective cube corner article and method of manufacture
US5914812A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1997 |
| Grant date | Jun 22, 1999 |
| Priority date | — |
| Expiry date | Aug 8, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/124
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A cube corner article and method of manufacturing the article from a series of directly machinable unitary substrates. The method of manufacture comprises the first step of providing an initial unitary directly machinable substrate of material suitable for forming retroreflective surfaces. Then, a first cube corner element array zone is formed having a plurality of geometric structures including cube corner elements. The zone is created by directly machining at least two sets of parallel grooves in the substrate. A replica of the cube corner element array zone is formed as an additional unitary substrate suitable for forming retroreflective surfaces. Portions of the replica substrate material are removed. The removal of these portions forms at least two intersecting cavities bounded by side walls in the replica at a depth at least that of the cube corner elements formed by the groove sets. Each cavity comprises at least one side wall which extends to a depth into the replica substantially equal to the deepest depth of any other intersecting cavity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.