博碩士論文 103226038 詳細資訊




以作者查詢圖書館館藏 以作者查詢臺灣博碩士 以作者查詢全國書目 勘誤回報 、線上人數:13 、訪客IP:3.235.228.219
姓名 李柏逸(Po-Yi Lee)  查詢紙本館藏   畢業系所 光電科學與工程學系
論文名稱 利用電控動態手紋結構製作雙穩態散射型液晶光閥之研究
(Studies of bistable scattering mode liquid crystal light modulators by electrically switchable dynamic fingerprint chiral textures)
相關論文
★ 液晶摻雜十二氫氧基硬酯酸於鍍有聚乙烯基咔唑薄膜液晶盒中之多穩態特性及其應用★ 利用偶氮苯摻雜膽固醇液晶製作光控線性偏振旋轉器
★ 利用扭轉型聚合物網絡液晶製作 偏振選擇性光散射之研究★ 中孔洞奈米粒子摻雜液晶之光電特性及其應用之研究
★ 藍相液晶摻雜旋性聚合物之表面穩定效應之研究★ 層列C型/層列C*型液晶摻雜偶氮苯材料之光電特性研究
★ 離子性材料對向列型液晶自發性配向及其應用之研究★ 膽固醇液晶摻雜離子性層列型液晶之動態散射特性研究
★ 膽固醇液晶及扭轉向列型液晶之線性偏振旋轉器★ 低操作電壓高分子分散型液晶及其應用之研究
★ 單面及雙面旋性聚合物穩固藍相液晶之光電特性★ 利用液晶相位空間光調制器實現波長及焦距可調之反射式Fresnel光學透鏡
★ 光控及電控散射型/吸收型液晶光閥之研究★ 利用雙扭轉向列型液晶製作可電光調控之線性偏振光液晶光圈
★ 電控及光控膽固醇液晶光閥特性與結構之研究★ 非對稱式液晶光電元件及其應用
檔案 [Endnote RIS 格式]    [Bibtex 格式]    [相關文章]   [文章引用]   [完整記錄]   [館藏目錄]   [檢視]  [下載]
  1. 本電子論文使用權限為同意立即開放。
  2. 已達開放權限電子全文僅授權使用者為學術研究之目的,進行個人非營利性質之檢索、閱讀、列印。
  3. 請遵守中華民國著作權法之相關規定,切勿任意重製、散佈、改作、轉貼、播送,以免觸法。

摘要(中) 隨著現今科技的發展,液晶技術日趨成熟,於智慧型窗戶應用的技術中,早有多種液晶散射光閥已成功被開發,最著名的為聚合物分散型液晶(Polymer Dispersed Liquid Crystals, 縮寫為PDLC),其多數利用照射UV光或加熱使單體聚合而引致液晶與聚合物發生相分離,並藉由外加電壓得到散射態和穿透態的切換。值得一提的是一般散射型液晶光閥須持續外加電壓方能維持其穿透度,換言之即造成能源的浪費,因此雙(多)穩態散射型液晶光閥的研究便受到相當的重視。
本論文提出利用電控動態手紋結構(Dynamic fingerprint chiral textures)製作一雙(多)穩態散射型液晶光閥,根據實驗結果,利用外加不同頻率的電場可在穿透態及散射態之間作切換,且在電場關閉後仍能維持永久穩定的穿透態及散射態,此動態手紋結構為本論文首先提出。本論文將分別討論(1)動態手紋結構的定義及其切換機制、(2)電控動態手紋結構的光電特性及(3)相關材料特性比較及其生成穩態的原因。其主要散射機制為利用外加高低頻交流電場切換動態手紋結構之區塊大小,外加高(低)頻交流電場可得較大(小)區塊之動態手紋結構而得穿透態(散射態),此外,由穿透態切換至散射態所需的電場振幅隨頻率降低而減小;反之,由散射態切換至穿透態所需的電場振幅隨頻率增加而減小。除關閉電壓後其穿透度可持續穩定外,該散射型光閥之散射能力與入射光偏振無關,且其穿透態無如上述PDLC有視角的限制。因此,本論文所提出之散射型液晶光閥具有可電控、永久穩態、廣視角、高對比及低操作電壓等特性,相信能在實際應用上有相當的潛力,如顯示器、電子書及電子紙等。
摘要(英) Liquid crystal (LC) technology is getting maturer and maturer nowadays due to its technological development. Many scattering mode LC light modulators are adopted to the application of smart windows. Among them, polymer dispersed LCs (PDLCs) is the most famous technique for such applications. Regarding the fabrication processes, phase separation of LCs and polymers by illuminating with UV light or heating is the most important approach. Additionally, the switching of the light modulator between transparent and scattering modes by applying an external electric field is also achieved. However, most of the scattering mode LC light modulators consume too much power to be suitable for practical application due to the continuous application of electric field. Restated, it causes large power consumption. Accordingly, bistable and multi-stable scattering mode LC light modulators have been paid much attention recently.
This study presents an electrically switchable and permanently stable scattering mode LC light modulator by dynamic fingerprint chiral textures (DFCT). According to the experimental results, stable transparent and scattering modes can be switched between each other after an electric field with different frequencies is applied. To the best of our knowledge, electrically switchable DFCT is demonstrated for the first time in this system. In this thesis, the following three parts, including (1) the definition of DFCT and its electric switching mechanism, (2) the electro-optical properties of electrically switchable DFCT, and (3) the comparison of the electro-optical properties between the other chiral materials and the causes for stabilization of DFCT, will be discussed in detail. Briefly, the main mechanism is the switching between large and small domains of DFCT by applying an electric field with different frequencies. With the application of electric field having high (low) frequency, the LC light modulator presents transparent (scattering) state due to the formation of large (small) domains of DFCT. Besides, the required amplitude to switch the light modulator from a scattering (transparent) state to a transparent (scattering) state decreases as the frequency of the applied electric field increases (decreases). In addition to the permanent stabilization after the applied field is switched off, such a LC light modulator has some other advantages, such as polarization-independent scattering, unlimited viewing angle in transparent mode, and others. Consequently, this study presents a scattering mode LC light modulator with the advantages of electrical switching, permanent stabilization, wide viewing angle, high contrast, low driving voltage, and so on. Considering the practical applications of LC devices, it is believed that such novel textures, DFCT, can be adopted to develop displays, e-books, e-papers, etc.
關鍵字(中) ★ 動態手紋結構
★ 雙穩態
★ 散射
★ 液晶
★ 光閥
關鍵字(英) ★ DFCT
★ bistability
★ scattering
★ liquid crystals
★ light modulators
論文目次 中文摘要 i
Abstract iii
誌謝 v
目錄 vi
表目錄 xi
圖目錄 xii
符號說明 xxi
第一章 緒論 1
§1-1 前言 1
§1-2 研究動機 1
§1-3 論文結構 2
第二章 液晶簡介 3
§2-1 液晶定義 3
§2-2 液晶分類 4
§2-2-1 盤狀分子 6
§2-2-2 棒狀分子 7
§2-3 液晶的光電特性 13
§2-3-1 液晶的光學異向性 13
§2-3-2 液晶的介電異向性 18
§2-3-3 溫度對液晶的影響 19
§2-3-4 連續彈性體理論 20
§2-3-5 Fréedericksz遷移(Fréedericksz transition) 22
第三章 實驗相關理論 24
§3-1 膽固醇液晶 24
§3-1-1 影響膽固醇液晶螺距的因素 24
§3-1-2 膽固醇液晶的各種結構 27
§3-1-3 膽固醇液晶各種結構間的切換 30
§3-2 手紋態結構膽固醇液晶 33
§3-2-1 手紋態結構膽固醇液晶之特性 34
§3-2-2 手紋態結構的種類 34
§3-2-3 橫向螺旋態結構(Uniform lying helix, 簡稱ULH結構) 37
§3-3 動態散射(Dynamic Scattering) 37
§3-4 偶氮苯材料(Azobenzene materials) 42
§3-4-1 光引致同分異構化(Photo-isomerization) 42
§3-4-2 光引致熱效應(Photo-induced thermal effect) 43
§3-4-3 偶氮苯手性分子 44
第四章 實驗方法與過程 45
§4-1 樣品製程 45
§4-1-1 材料介紹 45
§4-1-2 樣品製作 47
§4-2 實驗架構 51
§4-2-1 液晶空盒厚度量測 51
§4-2-2 偏光顯微鏡觀測樣品 53
§4-2-3 偶氮苯材料光致同素異構化方法 54
§4-2-4 液晶樣品光電特性量測 55
第五章 結果與討論 56
§5-1 電控動態手紋結構機制 56
§5-1-1 大區塊動態手紋結構(穩定穿透態) 56
§5-1-2 非完美平面態結構(穿透態) 58
§5-1-3 焦錐態結構(散射態) 60
§5-1-4 小區塊動態手紋結構(穩定散射態) 60
§5-1-5 電控動態手紋結構機制 63
§5-2 動態手紋結構光電特性 64
§5-2-1 利用直流或低頻交流電場將樣品切換至散射態 64
§5-2-2 利用高頻交流電場將樣品切換至穿透態 70
§5-2-3 利用改變外加振幅之頻率切換液晶光閥之灰階(Gray scale) 74
§5-2-4 光引致同分異構化 76
§5-2-5 偏振獨立之穿透及散射能力 77
§5-2-6 廣視角 78
§5-3 材料與配向膜的影響 80
§5-3-1 其他手性分子的比較 80
§5-3-2 配向膜對該散射型液晶光閥的影響 86
§5-3-3 動態手紋結構穩定因素 87
第六章 結論與未來展望 89
§6-1 結論 89
§6-2 未來展望 92
參考文獻 96
參考文獻 [1] G. H. Heilmeier, L. A. Zanoni, and L. A. Barton, “Dynamic scattering:A new electrooptic effect in certain classes of nematic liquid crystals,” Proc. IEEE 56, 1162 (1968).
[2] B. Bahoadur, Liquid crystals-applications and uses (World Scientific Press, 1990).
[3] F. Reinizer, “Beitrage zur kenntiniss des cholesterins,” Monatsh. Chem. 9, 421 (1888).
[4] O. Lehmam, “On flowing crystals,” Z. Phys. Chem. 4, 462 (1889).
[5] P. J. Collings, and Michael Hird, Introduction to liquid crystals chemistry and physics, (Taylor & Francis Ltd, 1997).
[6] S. Chandrasekhar, “Recent developments in the physics of liquid crystals,” Contemp. Phys. 29, 527 (1988).
[7] E. G. Virga, Variational theories for liquid crystals, (Chapman & Hall London, 1994).
[8] I. C. Khoo, and S. T. Wu, Optics and nonlinear optics of liquid crystals, (World Scientific, 1993).
[9] O. Francescangeli, S. Slussarenko, and F. Simoni, “Light-induced surface sliding of the nematic director in liquid crystals,” Phys. Rev. Lett. 82, 1855 (1999).
[10] M. Marinelli, and F. Mercuri, “Effects of fluctuations in the orientational order parameter in the cyanobiphenyl (nCB) homologous series,” Phys. Rev. E 61, 1616 (2000).
[11] H. Keller, “History of liquid crystals,” Mol. Cryst. Liq. Cryst. 21, 1 (1973).
[12] G. W. Gray, Thermotropic liquid crystals, (the Society of Chemical Industry 1987).
[13] W. H. de Jeu, Physical properties of liquid crystalline materials, (Gordon & Breach, 1980).
[14] 松本正一,角田市良,液晶之基礎與運用 (國立編譯館, 1996).
[15] P. Yeh, and C. Gu, Optics of liquid crystal displays, (John Wiley & Sons, Inc., 2006).
[16] G. R. Fowles, Introduction to modern optics, 2nd ed., (University of Utah, 1975).
[17] P. G. de Gennes, and J. Prost, The physics of liquid crystals, (Oxford University Press, 1993).
[18] L. M. Blinov, and V. G. Chigrinov, Electrooptic effects in liquid crystal materials, (Springer-Verlag Publishing Co., 1994).
[19] M. Hara, H. Takezoe, and A. Fukuda, “Forced Rayleigh scattering in nCB′s (n=5-9) with methyl red and binary mass diffusion constants,” Jpn. J. Appl. Phys. 25, 1756 (1986).
[20] V. Fréedericksz and A. Repiewa, “Theoretisches und experimentelles zur frage nach der natur der anisotropen flüssigkeiten,” Zeitschrift fur Physik 42, 532 (1927).
[21] R. B. Meyer, “Effects of electric and magnetic fields on the structure of cholesteric liquid crystals,” Appl. Phys. Lett. 12, 281 (1968).
[22] M. Gu, ““cholesteric” in the world of liquid crystal displays,” retrieved from http://www.personal.kent.edu/~mgu/ (2011).
[23] S. T. Wu, and D. K. Yang, Reflective liquid crystal displays, (John Wiley & Sons Ltd, 2001).
[24] A. Y. G. Fuh, C. H. Lin, and C. Y. Huang, “Dynamic pattern formation and beam-steering characteristics of cholesteric gratings,” J. Appl. Phys. 41, 211 (2002).
[25] 林啟湟,膽固醇手紋結構液晶薄膜及其應用之研究 (國立成功大學物理研究所, 2002).
[26] P. Rudquist, L. Komitov, and S. T. Lagerwall, “Volume-stabilized ULH structure for the flexoelectro-optic effect and the phase-shift effect in cholesterics,” Liq. Cryst. 24, 329 (1998).
[27] 李學文,穩定型橫向螺旋膽固醇液晶光柵之研究,(國立中山大學光電工程學系, 2012).
[28] C. T. Wang and T. H. Lin, “Bistable reflective polarizer-free optical switch based on dye-doped cholesteric liquid crystal,” Opt. Mat. Express 1, 1457 (2011).
[29] W. Helfrich, “Conduction-induced alignment of nematic liquid crystals:basic model and stability considerations,” J. Chem. Phys. 51, 4092 (1969).
[30] E. Dubois-Vilette, P. G. deGennes, and O. Parodi, “Hydrodynamic Instabilities of nematic liquid crystals under AC electric fields,” J. Physique 32, 305 (1971).
[31] Orsay Liquid Crystal Group, “Hydrodynamic instabilities in nematic liquids under AC electric fields,” Phys. Rev. Lett. 25, 1642 (1970).
[32] P. G. deGennes, “Electrohydrodynamic effects in nematics,” Comments Sol. St. Phys. 3, 148 (1971).
[33] G. Mie, “Contributions to the optics of turbid media particularly of colloidal metal solutions,” Ann. Phys. 25, 377 (1908).
[34] G. H. Heilmeier and J. E. Goldmacher, “A new electric field controlled reflective optical storage effect in mixed liquid crystal systems,” Proc. IEEE 57, 34 (1969).
[35] G. Dir, J. Wyscocki, J. Becker, W. Haas, J. E. Adams, L. Leder, B. Mechlowitz, F. Saeva and J. Dailey, “Cholesteric liquid crystal texture change displays,” Proc. SID 13, 105 (1972).
[36] D. Meyerhofer, and E. F. Pasierb, “Light scattering characteristics in liquid crystal storage materials,” Mol. Cryst. Liq. Cryst. 20, 279 (1973).
[37] E. Jakeman, and E. P. Raynes, “Electro-optic response times in liquid crystals,” Phys. Lett. 39A, 69 (1972).
[38] T. V. Galstyan, V. E. Drnoyan, and S. M. Arakelian, “Self-induced oscillations and asymmetry of the light angular spectrum in a dye doped nematic,” Phys. Lett. A 217, 52 (1996)
[39] Y. C. Liu, K. T. Cheng, H. F. Chen and A. Y. G. Fuh, “Photo- and electro-isomerization of azobenzenes based on polymer-dispersed liquid crystals doped with azobenzenes and their applications,” Opt. Express 22, 4404 (2014).
[40] Z. F. Liu, K. Hashimoto, and A. Fujishima, “Photoelectrochemical information storage using an azobenzene derivative,” Nature 347, 658 (1990).
[41] X. Tong, M. Pelletier, A. Lasia, and Y. Zhao, “Fast cis-trans isomerization of an azobenzene derivative in liquids and liquid crystals under a low electric field,” Angew. Chem. Int. Ed. Engl. 47, 3596 (2008).
[42] T. Enomoto, H. Hagiwara, D. A. Tryk, Z. F. Liu, K. Hashimoto, and A. Fujishima, “Electrostatically induced isomerization of azobenzene derivatives in langmuir-blodgett films,” J. Phys. Chem. B 101, 7422 (1997).
[43] 黃琬翎,摻雜偶氮材料在藍相液晶中之光電特性 (國立成功大學物理研究所, 2011).
[44] S. M. Morris, M. Qasim, K. T. Cheng, F. Castles, D. H. Ko, D. J. Gardiner, S. Nosheen, T. D. Wilkinson, H. J. Coles, C. Burgess, and H. Lee, “Optically activated shutter using a photo-tunable short-pitch chiral nematic liquid crystal,” Appl. Phys. Lett. 103, 101105 (2013).
[45] 許維婷,液晶盒厚度量測方法的研究 (國立成功大學光電科學與工程研究所, 2004).
[46] C. T. Wang, W. Y. Wang and T. H. Lin, “A stable and switchable uniform lying helix structure in cholesteric liquid crystals,” Appl. Phys. Lett. 99, 041108 (2011).
[47] J. Geng, D. Chen, L. Zhang, Z. Ma, L. Shi, H. Cao and H. Yang, “Electrically addressed and thermally erased cholesteric cells,” Appl. Phys. Lett. 89, 081130 (2006).
[48] A. Y. G. Fuh, Z. H. Wu, K. T. Cheng, C. K. Liu, and Y. D. Chen, “Direct optical switching of bistable cholesteric textures in chiral azobenzene-doped liquid crystals,” Opt. Express 21, 21840-21846 (2013).
[49] 吳宗翰,摻雜光敏偶氮染料的全光控膽固醇液晶顯示器 (國立成功大學物理研究所, 2012).
指導教授 鄭恪亭(Ko-Ting Cheng) 審核日期 2016-1-21
推文 facebook   plurk   twitter   funp   google   live   udn   HD   myshare   reddit   netvibes   friend   youpush   delicious   baidu   
網路書籤 Google bookmarks   del.icio.us   hemidemi   myshare   

若有論文相關問題,請聯絡國立中央大學圖書館推廣服務組 TEL:(03)422-7151轉57407,或E-mail聯絡  - 隱私權政策聲明