Perforated plate including embedded graphics
US7697711B2 · kind B2 · utility
1Cited by
22References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 13, 2006 |
| Grant date | Apr 13, 2010 |
| Priority date | — |
| Expiry date | Feb 11, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2499/15
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A perforated plate includes a plurality of holes divided into a first set of holes and a second set of holes. Each hole in the second set of holes has an area smaller than that of each hole in the first set; and the holes of the first and second sets are arranged with respect to one another to form a graphic pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.