Transmission efficiency enhancement by Fresnel lens design for an implanted piezoelectric ultrasonic power transmitter

碩士 === 臺灣大學 === 工程科學及海洋工程學研究所 === 98 === In recent years, there are many works focus on the improvement of the Biological technology. Furthermore, the integration of MEMS and Biological technology get more and more attentions in many research laboratories. Nowadays the implant biochips or medical fa...

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Bibliographic Details
Main Authors: Yi-Hung Liu, 劉怡宏
Other Authors: 李世光
Format: Others
Language:zh-TW
Published: 2010
Online Access:http://ndltd.ncl.edu.tw/handle/43507709460823772776
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Summary:碩士 === 臺灣大學 === 工程科學及海洋工程學研究所 === 98 === In recent years, there are many works focus on the improvement of the Biological technology. Furthermore, the integration of MEMS and Biological technology get more and more attentions in many research laboratories. Nowadays the implant biochips or medical facilities in micro scale are driven by batteries, which are not suitable for long-time use. In this study, the author constructs a piezoelectric ultrasonic power transmission system which can transmit power through the human body, the improvement can not only provide the power for long-time use but also for real-time use to many sensors. In this study, the author begins on clarifying the piezoelectric system and then integrated with the transmission theory for the ultrasonic power. PZT is chosen as the piezoelectric layer due to its high piezoelectric coefficient (d33), and agar plays the role of the human body. Fresnel half-wave band (FHWB) is introduced to be an improvement method for the power transmission efficiency, and there is a 5dB improvement observed from the modified design. A rectifier circuit makes the output power much useful, and the energy loss is less than 1.6mW for the circuit by using optimal load resistance.