| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a directional acoustic system which automatically adjusts sound quality of a directional speaker using an ultrasonic wave to high sound quality.SOLUTION: A directional acoustic system includes: a frequency characteristics adjustment part 4 which adjusts frequency characteristics of an input sound wave which is inputted; a modulation part 5 which modulates the input sound wave outputted from the frequency characteristics adjustment part 4; an ultrasonic transducer 8 which outputs the modulated input sound wave as an ultrasonic wave; and a microphone 9 which detects the outputted ultrasonic wave as audible sound. The frequency characteristics adjustment part 4 adjusts the frequency characteristics of the input sound wave so that the difference between the input sound wave before passing through the frequency characteristics adjustment part 4 and the audible sound detected by the microphone 9 becomes small.</p> |
