EP 0411671 A2 19910206 - Acoustic apparatus.
Title (en)
Acoustic apparatus.
Title (de)
Akustisches Gerät.
Title (fr)
Dispositif acoustique.
Publication
Application
Priority
- JP 10744190 A 19900425
- JP 20260189 A 19890804
- JP 20260289 A 19890804
Abstract (en)
An acoustic apparatus adapted to be heard only by a specific person or persons in one space without being worn by the user as in the case of an earphone. Sound signals emanating from the apparatus do not leak to the outside and are not affected by the surrounding moise. Basically, the apparatus is arranged such that a sound source (13) is disposed in one focus of a reflector (11, 35) having an ellipsoidal surface of revolution, and sound signals are heard at the other focus. To increase the number of specific hearers, if the central portion of the reflector (35) is made into a non-ellipsoidal surface of revolution, or a cross section having an ellipsoidal surface of revolution (45) is extended orthogonally to the cross section by a predetermined length, the range of the other focus expands. In addition, by arranging a plurality of reflectors (51A, 51B), it is possible to hear different sound signals within the effective areas of the respective reflectors (51A, 51B) without mutual interference of the sounds.
IPC 1-7
IPC 8 full level
G10K 11/28 (2006.01)
CPC (source: EP)
G10K 11/28 (2013.01)
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0411671 A2 19910206; EP 0411671 A3 19911009; EP 0411671 B1 19980513; CA 2022002 A1 19910205; CA 2022002 C 19991005; DE 69032304 D1 19980618; DE 69032304 T2 19990204
DOCDB simple family (application)
EP 90115030 A 19900803; CA 2022002 A 19900726; DE 69032304 T 19900803