Invisible acoustic screen for open-plan offices and the like
US5889869A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 1996 |
| Grant date | Mar 30, 1999 |
| Priority date | — |
| Expiry date | Jul 17, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K11/17875
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
The invisible acoustic screen for reducing sound leakage from handsfree telephones, loudspeaking computer terminals, and the like in a workspace includes a sound reducing apparatus comprising: a sound producing loudspeaker; a cancelling loudspeaker; a sensing microphone having an output; a delay circuit; and, an adaptive filter circuit having a value determined by a transfer function between the sound producing loudspeaker and the sensing microphone and by a transfer function between the cancelling loudspeaker and the sensing microphone; and the output of the sensing microphone being fed back to the adaptive filter circuit; and the received signal coupled through a delay circuit to the sound producing loudspeaker.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.