柔性結構空間域調控用光敏材料的研發與應用

Research and Development of Photo-sensitive Materials for Spatial Modulation of Flexible Structures

陳冠廷(Kuan-Ting Chen)

指導教授 ： 李世光

國立臺灣大學/工學院/工程科學及海洋工程學研究所/博士(2012年)

https://doi.org/10.6342/NTU.2012.00861

摘要

近年來，光場調控機制在許多元件設計上是常被應用之技術如光鉗、感測器、致動器、光敏電阻、壓電-光電元件等。其中光鉗之應用，利用光場所產生之力場約略在 pN 等級。壓電材料鋯鈦酸鉛(PZT)已被長時間的研究與開發於機電轉換之致動器、感測器與能源擷取裝置、電子產品。在文獻研究中得知壓電材料PZT之輸出力場可達mN至N等級，倘若壓電PZT之振形與輸出訊號能被光場所調控，其亦指著光場能利用調控壓電材料表面電場而產生高於光鉗九個數量級之力場。在本論文中，我們提出了創新之光調控PZT壓電感測器與致動器之構想，並研究不同光敏材料來隅合PZT壓電元件，嘗試開發與探討元件應用情境與光隅合特性。在所提出之光調控PZT壓電感測器與致動器是首例能以光場調控PZT壓電感測器與致動器，並利用不同的光圖形來控制壓電輸出振形與訊號。能利用光調控PZT壓電元件產生不同之振形，其在奈米、微米粒子的操控有著調控大力場之潛力，使其能達到實際應用上所需之力場。
在光調控PZT壓電感測器與致動器設計中，光敏材料是非常重要之研究對象。在論文中我們提出2種不同之光敏材料: (1) 液晶與染料之混合物(liquid crystal-spiropyran mixture)與(2) 酞菁氧鈦(titanium oxide phthalocyanine)作為PZT之光敏電極。液晶與染料之混合物及酞菁氧鈦(titanium oxide phthalocyanine)分別經照UV與可見光後之阻抗下降率可分別達0.3與0.01，由於不同光敏材料對於光反應有著其不同特性，其對於所設計之光調控PZT壓電感測器與致動器也有著不同影響，因此元件應用情境也隨著不同光敏材料的選擇而有所不同。論文中我們將詳細討論光敏材料液晶與染料混合物及酞菁氧鈦之電性分別與PZT隅合之特性，使得液晶與染料混合物及酞菁氧鈦可作為PZT之光敏電極，並能藉由光場來調控元件輸出。
本論文提出一光調控模態感測系統，主要由創新設計之光調控PZT壓電感測器所組成，光調控模態感測系統能利用不同照光時間與照光圖案即時操控產生不同模態之感測，此光調控模態感測系統在未來極具可應用於適應性系統與二維結構振動控制之潛能。此外，在文中亦討論利用不同光敏材料液晶與染料之混合物及酞菁氧鈦在光調控模態感測系統應用之不同表現特性。以液晶與染料混合物及酞菁氧鈦為基底之光調控PZT致動器之應用也詳細的討論，其中在DC趨動源下，我們成功的利用光調控PZT致動器之變形，這亦是首例利用光場調控PZT表面變形，其在未來可嘗試被應用於適應性光學系統之可形變鏡與微流體操控系統等。
本論文主要討論以液晶與染料混合物及酞菁氧鈦為基底之光調控PZT壓電感測器與致動器之不同應用與開發，使得輸出力場及振形能以光源照射不同的圖案來控制，並證實光敏材料其光電特性在與壓電PZT隅合後，能在所提出之應用情境中有所發揮，除系統皆被證實具備創新的應用特性外，亦說明了在系統實際應用面上所能帶來的突破。

關鍵字

鋯鈦酸鉛(PZT) ； 光調控PZT壓電感測器 ； 光調控PZT壓電致動器

並列摘要

Optical field modulation has been used in many applications in recent years, such as optical tweezers, sensors, actuators, light dependent resistor and piezo-phototronic devices. Optical tweezers can generate forces in approximately the pN range. Lead zirconate titanate (PZT) is a piezoelectric material that has been investigated for applications, such as electromechanical actuators, sensors, and energy generators. PZT typically generates output forces in the range of mN to N. If the spatial mode shapes and output signals of PZT could be modulated for specific applications and linked with optical inputs, then the magnitude of the output force could be modulated by more than nine orders of magnitude compared with optical tweezers. This thesis proposed the innovation of optically modulated PZT sensors/actuators and developed the proposed device by integrating photosensitive materials with PZT. In addition, the applications of these materials were also explored and discussed. This work represents the first time that PZT sensors/actuators have been controlled using optical inputs. The optically modulated PZT actuators developed here have great potential for applications, including the manipulation of nano- and micro-particles by controlling the spatial mode shapes of PZT.
Photosensitive materials are critical components for the design of optically modulated PZT sensors/actuators. Here, we propose two new photosensitive materials for integration with PZT, (1) a liquid crystal-spiropyran mixture (LC/SP) and (2) titanium oxide phthalocyanine (TiOPc). The impedance variation ratios of LC/SP mixture and TiOPc are 0.3 and 0.01 after UV and visible light irradiation respectively. The different properties of these photosensitive materials affect the device performance and can be applied for different applications. The electric properties of the LC/SP mixture and TiOPc are thus discussed in detail in terms of their suitability for PZT integration. The LC/SP mixture and TiOPc were used as the spatially modulated electrode of PZT in order to enable optical controllability.
This thesis proposes an optical modal sensor system composed of an optically modulated PZT sensor for one-dimensional vibration sensing. Based on this optically controllable modal sensor system, mode 1 and mode 2 sensors could be implemented and exchanged in situ in real time using different optical images and irradiation times. These optical modal sensor systems based on LC/SP mixtures and TiOPc have high potential for adaptive vibration control systems and two-dimensional vibration control. The performance of optically modulated PZT actuators based on LC/SP mixtures and TiOPc were also discussed and investigated in detail. The successful implementation of the DC effect allowed us to control the deformation using the optically modulated PZT actuator, which was tailored in situ in real time with different optical images. This technology has great potential for applications, such as deformable mirrors and microfluidic control.
Finally, this thesis explored and discussed various applications of optically modulated PZT sensors/actuators based on LC/SP mixtures and TiOPc. The output force and mode shapes of PZT sensors/actuators were modulated by introducing different optical images. The results strongly suggest that the materials developed in this thesis can perform well as optically modulated PZT sensors/actuators suitable for a variety of practical applications.

並列關鍵字

Lead zirconate titanate (PZT) ； Optically Modulated PZT sensors ； Optically Modulated PZT actuators

參考文獻

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