Acoustic Transducer

Acoustic Transducer

Dimension of the in-plane poled piezoelectric diaphragm: electrode width=60 μm; electrode spacing=250 μm; radius=3.5 mm.

The effective coupling coefficient is 3.08 %. The quality factor Q value is 39.96.

Schematic diagram of the test setup for evaluating the acoustic transmission performance of the devices. The setup was in an anechoic chamber. A B&K 4196 microphone with known sensitivity as reference.

Both the sensitivity and the sound pressure level (SPL= 20log(sound pressure /20 μPa)), peaks appear at the resonance of 13.71 kHz. The 1 kHz sensitivity of the d₃₃ mode diaphragm (126.21 μV/Pa), is nearly 20 times of the sensitivity (6.5 μV/Pa) of a d₃₁ mode thick film diaphragm with the same material and similar dimensions.

A 3 × 3 array was fabricated. Each element can be controlled independently. Directivity pattern of the array was tested. The array has the potential to be used as a phase array.

For more information, please refer to:

[1] Zhiyuan Shen, Jingyu Lu, Chee Wee Tan, Jianmin Miao, Zhihong Wang, “d₃₃ mode piezoelectric diaphragm based acoustic transducer with high sensitivity”, Sensor and Actuator A: Physical, 189, (2013), pp. 93-99.