Tamper-evident electric paper
US6419618B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 2000 |
| Grant date | Jul 16, 2002 |
| Priority date | — |
| Expiry date | Oct 31, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31504
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Tamper-evident electric paper is made of two sheets of electric paper bonded together, the bottom sheet of which includes a pattern. Any attempt to erase a writing on the top sheet of electric paper results in the pattern on the bottom sheet of electric paper being erased. Therefore any tampering by erasure of a writing on the tamper-evident electric paper is revealed by the absence of a portion of the pattern on the bottom sheet of electric paper. Single sheet tamper-evident electric paper has a complex pattern, such as an encryption, printed on a single sheet of electric paper. Any attempt to erase a writing on the electric paper also erases a portion of the encryption, thereby providing evidence of tampering.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.