| 摘要 |
PURPOSE:To contrive the conversion to a still sound by constituting the device so that in a transmitter/receiver inserted into an external auditory meatus, a sound from a loudspeaker for leading a voice to the external auditory meatus side offsets an external sound which passes through the inside of this transmitter/receiver from the outside of the transmitter/receiver and led to the external auditory meatus. CONSTITUTION:The device is provided with a signal processing circuit 6 for generating an acoustic wave whose phase is opposite to at least an eminent sound in waves by which an external sound is propagated into an external auditory meatus against outputs of microphones 5a, 5b. In transmitter/receivers 4a, 4b inserted into the external auditory meatus, a sound from a loudspeaker for leading a sound to the external auditory meatus offsets an external sound which passes through the inside of this transmitter/receiver from the outside of the transmitter/receiver and lead to the external auditory meatus. Also, a place for this offset is in a roughly closed space such as the external auditory meatus. In such a way, a still sound effect is large, and also, the accuracy required technically can be obtained easily. |
