Refractive acoustic devices for airborne sound.
نویسندگان
چکیده
We show that a sonic crystal made of periodic distributions of rigid cylinders in air acts as a new material which allows the construction of refractive acoustic devices for airborne sound. It is demonstrated that, in the long-wave regime, the crystal has low impedance and the sound is transmitted at subsonic velocities. Here, the fabrication and characterization of a convergent lens are presented. Also, an example of a Fabry-Perot interferometer based on this crystal is analyzed. It is concluded that refractive devices based on sonic crystals behave in a manner similar to that of optical systems.
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ورودعنوان ژورنال:
- Physical review letters
دوره 88 2 شماره
صفحات -
تاریخ انتشار 2002