| 摘要: | 本論文研究主題為提供隱私保護之液晶光電元件，全文共分為三部分，第一部分針對智慧窗進行研究，提出利用二色性染料摻雜液晶製作非對稱穿透式智慧窗，將二色性染料摻雜於液晶中，以LED燈泡搭配不同波段之窄頻濾波片組合為室內光源；室外參考光源D65乃為一寬頻光源，透過寬頻室外光源與窄頻室內光源經染料吸收後之穿透光譜差異，達到非對稱穿透式智慧窗之效果。因實驗上無法達成理想之非對稱效果，同時利用程式進行數值模擬，設計不同室內光源及染料吸收光譜，且將室內參考光源訂為6500K及3000K，室外參考光源訂為D65，用以優化智慧窗系統達成理想之非對稱效果。
本論文第二及第三部分係為隱私保護顯示器之研究，並將其細分為兩方向，其一為利用線性偏振光特性製作資訊保護液晶顯示器；其二為利用圓偏振光特性製作資訊保護顯示器。第二部分透過輸入隱藏資訊至反射式空間光調制器(reflective liquid crystal SLM，簡稱RLC-SLM)，使其提供二分之一波板之功能以調制入射RLC-SLM之線偏振光，顯示隱藏資訊與未顯示隱藏資訊部分之反射光偏振態將互相正交，輔以檢偏器即可見隱藏資訊。此外，將RLC-SLM置於偏光顯微鏡下觀察，推斷實驗上未使用檢偏器即可見隱藏資訊之問題為畫素間液晶排列不同導致。第三部分分為實驗及畫素設計兩者，實驗上利用寬頻四分之一波板薄膜將出射顯示器之線偏振光調制為圓偏振光，並透過由寬頻四分之一波板薄膜與線偏振片組合之圓偏振片達成隱私保護之效果。畫素設計的部分，將兩畫素合併為一複合畫素，於其上黏貼兩快軸軸向相互正交之寬頻四分之一波板薄膜，使奇數與偶數行畫素出射圓偏振光之旋性相反，透過調整點亮奇數或偶數行畫素，並搭配前述之圓偏振片，即可達成隱私保護顯示器之效果。
;The research topic, divided into three sections, of this thesis is about liquid crystal (LC) optoelectronic devices which provide the property of privacy protection. In the first section, we propose an asymmetrical transmission smart window based on dichroic dyes-doped LC. A LED light bulb and narrow-band filters for different wavelengths are combined to be the indoor light source. The standardized light, D65, is a broadband light source used as the outdoor light source. Asymmetrical property of the smart window can be achieved through the difference of transmission spectra between narrow-band indoor light source and broadband outdoor light source when the both light sources penetrate through the smart window from opposite sides. Since the ideal asymmetrical property could not be easily obtained experimentally, numerical simulations are conducted using the program to design different indoor light sources and dyes with suitable absorption spectra to optimize the smart window system ideally. For simulation, the indoor reference light sources with color temperatures of 6500K and 3000K are selected, and the outdoor reference light source is set to be the standardized light, D65. The second and third sections in this thesis report two types of displays with privacy protection which are designed according to the properties of linearly polarized light and circularly polarized light. Briefly, the privacy information is displayed on a reflective liquid crystal spatial light modulator (RLC-SLM), playing the role of a half-waveplate to modulate the polarization state of the reflective light. Therefore, the polarization states of the reflective lights with and without the privacy information are mutually orthogonal, which is the key point of the display reported in the second section. In addition, the reflective SLM with the displayed information has also been observed under a polarized optical microscopy (POM). According to the observation, it can be concluded that the visible privacy information, which can be viewed on the screen without any analyzer in the experiment, is caused by the differences of LC alignment between the adjacent pixels experimentally. The third section is subdivided into two parts for detailed discussion, including experiments and pixel-designs. In the experiment part, the linearly polarized light emitted from the display is modulated to circularly polarized light by using a broadband quarter-waveplate film. To accomplish the property of privacy protection, the combination of the broadband quarter-wave plate film and the polarizer to be a circular polarizer is needed. For the pixel design, the two pixels in odd and even rows are combined into one composite pixel beneath different broadband quarter-waveplate films with two orthogonal fast axes, so that the pixels in odd and even rows emit circularly polarized light with opposite handednesses. Finally, with the adjustment of the output light intensities of the pixels in odd and even rows, the privacy information can be viewed on the privacy-protected display with a circular polarizer. |
