| 摘要 |
PROBLEM TO BE SOLVED: To provide a personal acoustic system for a vehicle, in which only "the specific crew (e.g., only a driver)" is allowed to listen to audible sounds (voices, music or the like). SOLUTION: An ultrasonic wave amplitude-modulated in accordance with an audio signal is radiated from an ultrasonic loudspeaker 1 for the head installed above the head of a driver only toward the head α of the driver. Then, an amplitude component contained in the ultrasonic wave is demodulated not in the air but in the head α (cranial bones or the like) of the driver, and the head α (cranial bones or the like) of the driver can be vibrated by the amplitude component contained in the ultrasonic wave, so that only the driver is allowed to listen to "audible sounds" based on the "audio signal that becomes a sound source". Thus, only the driver can obtain audio information of navigation voices or traffic information or only the driver can enjoy music or radio without troubling the other crew. COPYRIGHT: (C)2011,JPO&INPIT |
