| 摘要 |
PURPOSE:To promptly, high-accurately, and stably detect the change of the direction of the head part of a listener by calculating the above-mentioned change based on the phase difference between the output signals of a pair of microphones to be arranged at two parts in the head part to pick up a detecting signal to be outputted from a detecting sound source. CONSTITUTION:For a headphone device 2, first and second microphones 3 and 4 are arranged for mutually separated two parts. A speaker 5 to be the detecting sound source is fixed and arranged to a position separated from the listener. An ultrasonic signal in a non-audible band is supplied from an ultrasonic signal source 7 to this speaker 5, and the speaker 5 outputs an ultrasonic wave to be the detecting signal. This ultrasonic wave is a so-called acoustic wave such as a bust wave for which the detection of its phase is made possible. The output signals of the microphones 3 and 4 are the signals obtained by picking up the acoustic wave to be outputted from the speaker 5, and an arithmetic unit 8 calculates the change of the direction of the head part based on the phase difference between the output signals of both the microphones and respectively processes the acoustic signals of a left channel and a right channel from an acoustic signal supplying source 16 based on transmission characteristics corresponding to the calculated direction of the above-mentioned head part. |
