| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an improved noise reduction system including a headphone, in which mechanical protection of a microphone is secured, and which is comfortable for a user. <P>SOLUTION: An active noise reduction system includes an earphone. The earphone has a cup-like housing with an aperture; a transmitting transducer for converting electrical signals into acoustical signals to be radiated to the user's ear, which is arranged at the aperture of the cup-like housing thereby defining an earphone cavity; and a receiving transducer which converts acoustical signals into electrical signals and which is arranged within the earphone cavity; a first acoustical path which extends from the transmitting transducer to the ear and which has a first transfer characteristic; a second acoustical path which extends from the transmitting transducer to the receiving transducer and which has a second transfer characteristic; and a control unit which is electrically connected to the receiving transducer and the transmitting transducer and which compensates for the ambient noise by generating a noise reducing electrical signal supplied to the transmitting transducer. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
