以TiOPc/壓電圓板設計可撓鏡的研發

Abstract

本論文嘗試開發具備以光學場調制(modulate)力學場能力的複合材料並將其製作為致動器，其目的為以使用光學場調制的力學場方式來取代傳統透過電極陣列來驅動可撓鏡的操作方式。該複合材料是透過結合TiOPc/copolymer薄膜以及壓電材料PZT (Lead Zirconate Titanate)來製作。本文針對光電導材料(photoconductive material) TiOPc (Titanyl Phthalocyanine)薄膜做了詳盡的電學阻抗分析實驗，以精密阻抗分析儀(Agilent 4294A)進行量測，並建立其等效電路。我們整理並分析TiOPc薄膜的電學特性與薄膜製程參數間的關聯，並建立TiOPc薄膜電學性質變化與光強度間的關係。 我們以電學阻抗匹配的方式來決定TiOPc薄膜的製程參數，製作出TiOPc/壓電致動可撓鏡，並建立其致動器方程式。可撓鏡性能的驗證是以光學量測系統：電子斑點干涉儀(Electronic Speckle Pattern Interferometer, ESPI)來進行可撓鏡的表面變形量測。由實驗結果證實，本研究中所製備的可撓鏡元件可以照光的方式來調制力學場的變化。為了達成可撓鏡的應用，我們試著設計不同的照光圖形來使可撓鏡的表面變形形狀相似於三階像差(aberration)的波前(wavefront)形狀，分析的方式是使用CODE V光學軟體做Zernike多項式(Zernike polynomial)的曲面擬合計算。由結果可得知，本研究所製作之光調控式可撓鏡具備對場曲、像散等三階像差進行補償的能力。

In this thesis, we intended to modify the actuating structure of a traditional deformable mirror which was actuated by an electrode-array. We developed a new smart composite material which could use optical illumination to modulate the spatially distributed actuating forces. The smart composite material is composed of photoconductive material TiOPc (Titanyl Phthalocyanine) and piezoelectric material PZT (Lead Zirconate Titanate) to perform Opto-Piezo modulation. More specifically, spatial modulation in this smart composite is done by using a light field instead of an electrical field to modulate the spatial distribution of the force field created. To enhance the effect of a light field modulated force field, the electrical impedance of TiOPc/copolymer thin film and piezoelectric lamina must match. The electrical impedance of TiOPc thin film was measured by Agilent 4294A Precision Impedance Analyzer and an equivalent circuit model was established. According to the experimental results of the measured electrical impedance, we built the relationship between the parameters of thin film process and the equivalent R-C value in the equivalent circuit model. Further experiments were performed to establish the relationship between light intensity and the R-C value. An actuator equation was also developed for the spatially modulated TiOPc/PZT actuator. ESPI (Electronic Speckle Pattern Interferometer) was then introduced to test the ability of the spatially modulated TiOPc/PZT actuator. The experimental results confirmed the ability of spatial modulation. Furthermore, we used CODE V to perform surface fitting of Zernike polynomial. The spatial modulation by light achieved was identified to be able to compensate third-order aberration such as field curvature and astigmatism.