Electric sound converter
US6081604A · kind A · utility
134Cited by
3References
21Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 18, 1998 |
| Grant date | Jun 27, 2000 |
| Priority date | — |
| Expiry date | Mar 18, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R1/1008
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A head-phone having a case member storing therein a headphone unit, wherein a coating film containing a light discolor pigment to be discolored by irradiation of sun light is provided on the whole surface or a predetermined surface of the case member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.