攝護腺癌為台灣男性前五大癌症之一。目前常用治療攝護腺癌的方式為經直腸高強度聚焦超音波(Transrectal HIFU)，其作法是將探頭伸入直腸中，超音波使組織瞬間升溫而使得細胞凋亡。且因具有高度聚焦的特性，可以減少對周圍組織的影響，降低副作用。因此超音波治療成為近年來常用的一種治療方式。目前的商用設備將探頭以機械移動的方式沿著直腸前後移動，以及旋轉來盡量涵蓋治療區域，而這種方式可能會有磨傷直腸壁的風險。因此若能使用單一陣元的探頭來達到改變聚焦長度以及轉向的特性，在探頭就定位之後，以探頭自身的變焦與轉向來涵蓋治療區域，降低直腸壁損傷的風險。
液體鏡頭因其可控制液體形狀的特性，製作成鏡頭後具有使超音波變焦與轉向的潛力，包含薄膜液壓式液體鏡頭、電濕潤式液體鏡頭。然而在現有的研究中，薄膜液壓式液體鏡頭無法達成較快速的變焦及轉向功能，電濕潤式液體鏡頭目前無法同時做到變焦與轉向兩種功能，因此本研究希望開發新式之電濕潤式液體鏡頭，使超音波變焦與轉向，並能以較低電壓來驅動。
本研究設計一顆電濕潤式液體鏡頭搭配自製5.5 MHz、7.2 mm孔徑之平面式單陣元探頭作為發射源。鏡頭內以水與矽油兩種不同聲速的液體形成透鏡，並以給予兩側電壓形成電濕潤現象，來控制兩液體介面的曲率半徑或偏折角。在給予液體鏡頭48 V的低電壓內，可使超音波聚焦長度在26 ~ 32.9 mm變化，在分別給予液體鏡頭兩側0 V與60 V的電壓組合下可達最多5∘的轉向角，並且可以在維持轉向的情況下同時達到變焦的效果，聚焦長度在25 ~ 29 mm中變化，符合本研究設定在單陣元探頭上達成變焦與轉向兩種功能的液體鏡頭。未來將透過改善鍍膜參數來實現更大的變焦範圍及轉向角，並且拓展成二維的轉向功能。

Prostate cancer is one of the most frequently diagnosed cancers in the male population in Taiwan. One of the most common therapies is transrectal high intensity focused ultrasound. A transducer is inserted into rectum to deliver high energy, which rapidly raises the temperature of the prostate and causes necrosis. It also has fewer side effects than other treatments because it is highly focused on a small area. Current commercial devices move the transducer back and forth inside the rectum to cover the whole prostate. However, this approach may cause rectum injury. Thus, if a single element transducer with variable focus and steering is used, it can cover the entire prostate without moving the transducer frequently.
Liquid lens has the potential to change the focal point and steer the ultrasound due to the ability to control the shape of liquid. In current research, membrane liquid lens doesn’t have the ability to change the focal point rapidly or steer ultrasound by membrane liquid lens. Electrowetting liquid lens only have one of the ability to change focus or steer, not both in one device. This research designs a new type of electrowetting liquid lens with variable focus and steering ability with a low applied voltage in one device.
In this research, an electrowetting liquid lens working with a 5.5 MHz, 7.2 mm aperture homemade single element planar transducer was designed. Two materials with different speed of sound, such as water and silicone oil, forms a liquid interface as a lens, and the liquid interface is controlled by electrowetting. The focal length of ultrasound varies from 26 mm to 32.9 mm by applying voltage to liquid lens within 48 V. Also the steering angle of ultrasound can reach a maximum steering angle of 5∘by applying 0 V and 60 V to both sides of the liquid lens. Furthermore, the focal length can be varied from 25 to 29 mm while maintaining the steering angle. These results approve the design of electrowetting liquid lens with variable focus and steering ability. Future work includes improving fabrication parameters to obtain larger focal range and steering angle, and developing two-dimension steering.

摘要 i
Abstract ii
誌謝 iv
圖目錄 viii
表目錄 xiii
第1章 、緒論 1
1.1 攝護腺癌 1
1.2 目前商用的治療設備與限制 1
1.3 超音波聚焦：聲透鏡 4
1.3.1 薄膜液壓式 7
1.3.2 電濕潤式液體鏡頭 7
1.4 電濕潤原理 8
1.4.1 基板 9
1.4.2 絕緣層 11
1.4.3 疏水層 12
1.5 液體鏡頭之比較 14
1.6 液體鏡頭目前在超音波領域的應用 14
1.7 研究目的與動機 18
1.8 論文架構 19
第2章 、實驗材料與方法 21
2.1 概論 21
2.2 超音波探頭製作 21
2.3 超音波模擬與聲場量測 22
2.3.1 超音波模擬 22
2.3.2 聲場掃描 24
2.4 薄膜液壓式液體鏡頭之製作 25
2.4.1 鏡頭組裝 26
2.4.2 曲率量測與聲場掃描 27
2.5 電濕潤式液體鏡頭之組成 29
2.5.1 電極板 29
2.5.2 上下蓋材料選擇 30
2.5.3 液體選擇 31
2.6 電極板製作 31
2.6.1 絕緣層 32
2.6.2 疏水層 34
2.7 電極板性能測試 34
2.8 鏡頭組裝及驅動方式 35
2.8.1 表面張力測量 35
2.8.2 鏡頭驅動方式 36
2.8.3 曲率量測與聲場掃描 38
第3章 、結果 40
3.1 超音波探頭製作與模擬驗證 40
3.2 薄膜液壓式鏡頭 43
3.2.1 曲率量測 43
3.2.2 聲場模擬及聲場掃描 44
3.3 電極板特性測量 47
3.3.1 絕緣層厚度 47
3.3.2 疏水層厚度 49
3.3.3 接觸角量測 49
3.4 電濕潤式鏡頭特性量測 53
3.4.1 表面張力量測 53
3.4.2 直流電驅動之曲率量測 54
3.4.3 頻率響應 55
3.4.4 交流電驅動之曲率量測 56
3.4.5 穩定性 59
3.4.6 響應時間 60
3.4.7 左右不同電壓之偏折角量測 61
3.5 電濕潤式鏡頭聲場 66
3.5.1 聚焦聲場掃描 66
3.5.2 超音波轉向聲場掃描 74
3.5.3 超音波同時轉向與變焦 76
第4章 、結論與未來工作 79
4.1 結論 79
4.2 未來工作 80
第5章 、參考文獻 81
附錄一、Turnitin檢測結果 88

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