Method and apparatus for attentuating external origin noise reaching the eardrum, and for improving intelligibility of electro-acoustic communications
US4833719A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1987 |
| Grant date | May 23, 1989 |
| Priority date | — |
| Expiry date | Sep 23, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K2210/504
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
The invention relates to a method and to apparatus for attenuating externally originating noise reaching the eardrum while still enabling communication via an electro-acoustic path. Apparatus according to the invention comprises passive attenuation means disposed about each ear and delimiting a cavity (10). In addition it includes active attenuation means comprising a loudspeaker (6) placed inside the cavity (10) and a microphone (8) placed in the external ear duct or at the inlet thereto, said loudspeaker and microphone being interconnected by a constant gain amplifier (11) and an active analog filter (12) of the polynomial type, with the passive components thereof being designed to provide a given transfer function. One application lies in the construction of protective headsets fitted with incorporated loudspeakers enabling electro-acoustic communication.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.