Transparent retroreflective sheets containing directional images and method for forming the same
US4688894A · kind A · utility
76Cited by
6References
17Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 13, 1985 |
| Grant date | Aug 25, 1987 |
| Priority date | — |
| Expiry date | May 13, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06K19/14
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A directional image is created in substantially transparent retroreflective sheeting comprising a monolayer of microlenses and a partially light transmissive mirror disposed at the rear surfaces of at least some of said microlenses. The image is created by irradiation of the sheeting with a laser beam to form axial markings associated with at least some of the microlenses. The image may be formed in sheeting which has been applied to a document as an overlay.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.