| 摘要(英) |
The research topics in this thesis include the following two sections. In the first section, the liquid crystal (LC) textures existing in the electrically controllable cholesteric LC (CLC) light shutter and the corresponding switching mechanism are discussed in detail. According to the measurements of transmittance versus applied voltage curves, and the images obtained by a polarized optical microscopy, the applied voltage range of each texture was elucidated. Furthermore, the switching mechanism was also proposed based on the obtained transmittance versus time curves. In addition, the detailed discussions described in Chapter 5 include the five kinds of LC textures, they are spiral-like fingerprint textures, grid-like fingerprint textures, multi-domain like fingerprint textures, field-induced fingerprint textures, and homeotropic textures. Moreover, the CLC light shutter mentioned in this thesis has three kinds of stable states, and the capabilities of transmission and scattering of each state are different. By using the mentioned opto-electronic characteristics, the proposed CLC light shutter has great potential for the application of the augmented reality (AR), which has also discussed in Chapter 6.
The second section of the thesis is the study of optically controllable CLC light shutter. This study focuses on the influences of light shutter architecture resulted from the adopted polymer networks. The proposed CLC light shutter can be switched between transparent and scattering states under the illumination of UV lights. The switching mechanism of the CLC light shutter is based on the photo-isomerization effect and the photo-induced thermal effect of the doped push-pull azobenzene molecules. Owing to the above-mentioned effects, the scattering and transparent states of the CLC light shutter are successfully achieved by the focal conic textures and the isotropic state, respectively. In order to discuss the photo-isomerization effect individually, the temperature controller was utilized to maintain the ambient temperature and to remove the influence resulted by the photo-induced thermal effect on the CLC light shutter. The influences of photo-isomerization and photo-induced thermal effect of the light shutter can be observed simultaneously, resulted from the absence of the temperature controller. The proposed CLC light shutter has the capability to adjust transmittance automatically through the environmental variation, the possibility of applications of smart windows and future works according to its optical characteristics are also proposed in Chapter 6.
|
| 參考文獻 |
[1] F. Reinitzer, “Beiträge zur Kenntniss des Cholesterins,” Monatsh. Chem, 9, 421-441 (1888).
[2] D. Dunmur and T. Sluckin, “Soap, Science, and Flat-screen TVs: a history of liquid crystals,” Oxford University Press, USA (2011).
[3] D. Andrienko, “Introduction to liquid crystals,” J. Mol. Liq. 267, 520–541 (2018).
[4] P. G. de. Gennes and J. Prost, “The Physics of Liquid Crystal,” 2nd ed., Oxford University Press, New York (1993).
[5] A.Yariv and P. Yeh, “Optical Waves in Crystals,” John Wiley & Sons, Inc., New York (1983).
[6] P. Yeh and C. Gu, “Optics of Liquid Crystal Displays,” John Wiley & Sons, Inc., New York (1999).
[7] H.-S. Kitzerow and C. Bahr, “Chirality in Liquid Crystals,” Springer, New York (2001).
[8] G. Vertogen, “Elastic Constants and the Continuum Theory of Liquid Crystals,” Physica 117A, 227-231 (1983).
[9] P. J. Collings and M. Hird, “Introduction to Liquid Crystals: Chemistry and Physics,” CRC Press, London (1997).
[10] D.‐K. Yang and S.‐T. Wu, “Fundamentals of Liquid Crystal Devices,” John Wiley & Sons (2014).
[11] R. J. A. Tough and M. J. Bradshaw, “The determination of the order parameters of nematic liquid crystals by mean field extrapolation,” Journal de Physique 44, 447-454 (1983).
[12] D. J. Griffiths, “Introduction to Electrodynamics,” Pearson (2017).
[13] L. M. Blinov and V. G. Chigrinov, “Electrooptic Effects in Liquid Crystal Materials,” Springer, New York (1994).
[14] A. Ryabchun and A. Bobrovsky, “Cholesteric Liquid Crystal Materials for Tunable Diffractive Optics,” Adv. Optical Mater. 6, 1800335 (2018).
[15] A. Y.-G. Fuh, C.-H. Lin, and C.-Y. Huang, “Dynamic Pattern Formation and Beam-Steering Characteristics of Cholesteric Gratings,” Jpn. J. Appl. Phys. 41, 211-218 (2002).
[16] I. Gvozdovskyy, O. Yaroshchuk, M. Serbina, and R. Yamaguchi, “Photoinduced helical inversion in cholesteric liquid crystal cells with homeotropic anchoring,” Opt. Express 4, 3499-3508 (2012).
[17] G. Carbone, D. Corbett, S. J. Elston, P. Raynes, A. Jesacher, R. Simmonds, and M. Booth, “Uniform Lying Helix Alignment on Periodic Surface Relief Structure Generated via Laser Scanning Lithography,” Mol. Cryst. Liq. Cryst. 544, 1025-1037 (2011).
[18] G. H. Heilmeier and L. A. Zanoni, “Guest-Host Interactions in Nematic Liquid Crystals. A New Electro-Optic Effect,” Appl. Phys. Lett. 13, 91-92 (1968).
[19] 李伯逸，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(國立中央大學光電科學與工程學系 2016).
[20] B. I. Senyuk, I. I. Smalyukh, and O. D. Lavrentovich, “Switchable two-dimensional gratings based on field-induced layer undulations in cholesteric liquid crystals,” Opt. Lett. 30, 349-351 (2005).
[21] D. L. White and G. N. Taylor, “New absorptive mode reflective liquid-crystal display device,” J. Appl. Phys. 45, 4718-4723 (1974).
[22] S.-W. Oh, J.-M. Baek, and T.-H. Yoon, “Sunlight-switchable light shutter fabricated using liquid crystals doped with push-pull azobenzene,” Opt. Express 24, 26575-26582 (2016).
[23] Y.-D. Chen, A. Y.-G. Fuh, and K.-T. Cheng, “Optically and thermally controllable light scattering based on dye-doped liquid crystals in poly(N-vinylcarbazole) films-coated liquid crystal cell,” Opt. Express 20, 26252-26260 (2012).
[24] S. D’Elia, V. Barna, N. Scaramuzza, G. Strangi, and R. Bartolino, “The influence of drying temperature on the close packed structure of silanized monolayers deposited on indium tin oxide (ITO) substrates,” J. Mater. Res. 24, 2784-2794 (2009).
[25] W. Helfrich, “Deformation of Cholesteric Liquid Crystals with Low Threshold Voltage,” Appl. Phys. Lett. 17, 531-532 (1970).
[26] J.-H. Huh, “Electrohydrodynamic Instability in Cholesteric Liquid Crystals in the Presence of a Magnetic Field,” Mol. Cryst. Liq. Cryst. 477, 67-76 (2007).
[27] Y.-C. Hsiao and W. Lee, “Polymer stabilization of electrohydrodynamic instability in non-iridescent cholesteric thin films,” Opt. Express 23, 22636-22642 (2015).
[28] W.-F. Cheng, J.-C. Lai, S. T.-F. Jie, C.-K. Liu, and K.-T. Cheng, “Scattering-/aborption-mode light shutters based on dye-doped fingerprint chiral textures,” Dyes and Pigments 163, 78-85 (2019).
|
[Endnote RIS 格式]
[相關文章]
[文章引用]
[完整記錄]
[館藏目錄]
至系統瀏覽論文 (2024-7-1以後開放)
plurk
funp
live
udn
HD
myshare
netvibes
friend
youpush
delicious
baidu
Google bookmarks
del.icio.us
hemidemi
facebook
twitter
google
reddit