Color display, authentication medium, and method of determining authenticity of color display
US11977938B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 2022 |
| Grant date | May 7, 2024 |
| Priority date | — |
| Expiry date | May 18, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/20
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A forming mold has a surface in contact with a deposited film, a part or an entire part being a first wavy surface. A wave period of the first wavy surface is in a range of 250 nm or more and 500 nm or less. The deposited film conforms to the surface of the forming mold. The first wavy surface includes a plurality of rib surfaces, a plurality of groove surfaces, and a plurality of taper surfaces connecting the rib surfaces to the respective groove surfaces. The deposited film has a peak zone, a valley zone, and a transition zone. One of the peak zone, the valley zone, and the transition zone and another one of the peak zone, the valley zone, and the transition zone are different or has portions different in thickness and/or volume density.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.