碩士 / 國立成功大學 / 機械工程學系碩博士班 / 93 / PVDF films are frequently used piezoelectric materials as sensing materials for fabricating hydrophones. They have a number of advantages such as lower acoustic impedance, flexibility in shaping, high mechanical strength, and commercial availability in a variety of film thickness, surface electrode coating, protection coating layers, etc. In this work, we use an excimer laser micro-machining system to fabricate PVDF hydrophones and hydrophone arrays. The metal electrodes deposited on both sides of the polarized PVDF have been patterned by an excimer laser with a direct writing and scanning method. Both needle type and membrane type PVDF hydrophones or hydrophone arrays are then conveniently constructed. We also fabricate several ultrasonic transducers for producing a uniform sound pressure field on the sensing element of hydrophones. The characteristics of the fabricated hydrophones, especially the sensitivity, have been determined at frequency ranging from 1 MHz up to 20 MHz. These data are correlated to several important parameters, such as the PVDF film thickness, area size of sensing element, and backing material properties.
To characterize the fabricated PVDF hydrophones, an ultrasound detect system under water for the hydrophones are set up. The investigations include theoretical analysis and modeling, computer software simulation, hydrophone design and fabrication, experiment testing, standard calibration, and system integration. A number of phenomena of the fabricated PVDF hydrophones and hydrophone arrays are observed.
| Identifer | oai:union.ndltd.org:TW/093NCKU5490117 |
| Date | January 2005 |
| Creators | Shiang-Wen Huang, 黃祥紋 |
| Contributors | Yung-Chun Lee, 李永春 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 127 |
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