Near-Field Acoustic Holography of a Vibrating Drum Head
نویسنده
چکیده
This paper explains the design and construction of a phase-sensitive near-field acoustic holography apparatus. By using phase-sensitive lock-in amplifier techniques to record the complex signals of pressure and particle velocity microphones over an extended spatial region, small vibrations can be imaged using the acoustical properties of said vibrations. The apparatus is tested on a vibrating drumhead and the first few eigenmodes are visualized.
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تاریخ انتشار 2009