| 摘要 |
PROBLEM TO BE SOLVED: To generate audible sound having sufficient sound pressure irrespective of distance from a radiator in an audible area. SOLUTION: An audio signal showing the audible sound generated by a sound source 1 is input in a modulator 2, a modulation signal using ultrasonic wave as carrier wave is generated and the modulation signal is amplified by an amplifier 3. One modulation signal is input in a plurality of radiators 4 from the amplifier 3. The radiators 4-7 are provided at each interval so that each radiated audible sound is overlapped when the audible sound using the ultrasonic wave as the carrier wave is radiated, respectively. COPYRIGHT: (C)2007,JPO&INPIT |
