ACOUSTIC SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an acoustic system wherein presence is enhanced by generating sounds while limiting a listener. SOLUTION: The acoustic system comprises: an acoustic device 2 for modulating a carrier belonging to an ultrasonic band by using an audible sound signal and emitting the modulated ultrasonic signal as a sonic wave with super-directivity; a human sensor 1 for sensing that a human enters a specific area located in an audible area where the sonic wave reaches from the acoustic device 2; and a processor 25 for forcing the acoustic device 2 to radiate the sonic wave if a notification is received from the human sensor 1 that a human has entered the specific area. COPYRIGHT: (C)2005,JPO&NCIPI