Browse > Article
http://dx.doi.org/10.3807/COPP.2019.3.1.066

Flexible Liquid Crystal Displays Using Liquid Crystal-polymer Composite Film and Colorless Polyimide Substrate  

Kim, Tae Hyung (Graduate School of Flexible & Printable Electronics Engineering, Chonbuk National University)
Kim, Minsu (Applied Materials Institute for BIN Convergence, Department of BIN Convergence Technology, Department of Polymer-Nano Science and Technology, Chonbuk National University)
Manda, Ramesh (Applied Materials Institute for BIN Convergence, Department of BIN Convergence Technology, Department of Polymer-Nano Science and Technology, Chonbuk National University)
Lim, Young Jin (Applied Materials Institute for BIN Convergence, Department of BIN Convergence Technology, Department of Polymer-Nano Science and Technology, Chonbuk National University)
Cho, Kyeong Jun (Applied Materials Institute for BIN Convergence, Department of BIN Convergence Technology, Department of Polymer-Nano Science and Technology, Chonbuk National University)
Hee, Han (Advanced Materials R&D, LG Chem)
Kang, Jae-Wook (Graduate School of Flexible & Printable Electronics Engineering, Chonbuk National University)
Lee, Gi-Dong (Department of Electronics Engineering, Dong-A University)
Lee, Seung Hee (Applied Materials Institute for BIN Convergence, Department of BIN Convergence Technology, Department of Polymer-Nano Science and Technology, Chonbuk National University)
Publication Information
Current Optics and Photonics / v.3, no.1, 2019 , pp. 66-71 More about this Journal
Abstract
Application of liquid crystal (LC) materials to a flexible device is challenging because the bending of LC displays easily causes change in thickness of the LC layer and orientation of LCs, resulting in deterioration in a displayed image quality. In this work, we demonstrate a prototype device combining a flexible polymer substrate and an optically isotropic LC-polymer composite in which the device consists of interdigitated in-plane switching electrodes deposited on a flexible colorless polyimide substrate and the composite consisting of nano-sized LC droplets in a polymer matrix. The device can keep good electro-optic characteristics even when it is in a bending state because the LC orientation is not disturbed in both voltage-off and -on states. The proposed device shows a high potential to be applicable for future flexible LC devices.
Keywords
Flexibility; Optically isotropic liquid crystal (OILC); Colorless polyimide (CPI); In-plane switching (IPS);
Citations & Related Records
연도 인용수 순위
  • Reference
1 Y. Tanabe, H. Furue, and J. Hatano, "Optically isotropic liquid crystals with microsized domains," Mater. Sci. Eng. B-Solid. 120, 41-44 (2005).   DOI
2 S. W. Choi, S. I. Yamamoto, T. Iwata, and H. Kikuchi, "Optically isotropic liquid crystal composite incorporating in-plane electric field geometry," J. Phys. D: Appl. Phys. 42, 112002 (2009).   DOI
3 M. Kim, B. G. Kang, M. S. Kim, M. K. Kim, P. Kuar, M. H. Lee, S. W. Kang, and S. H. Lee, "Measurement of local retardation in optically isotropic liquid crystal devices driven by in-plane electric field," Curr. Appl. Phys. 10, E118-E121 (2010).   DOI
4 N. H. Park, S. C. Noh, P. Nayek, M.-H. Lee, M. S. Kim, L.-C. Chien, J. H. Lee, B. K. Kim, and S. H. Lee, "Optically isotropic liquid crystal mixtures and their application to high-performance liquid crystal devices," Liq. Cryst. 42, 530-536 (2015).   DOI
5 K. D. Harris, A. L. Elias, and H. J. Chung, "Flexible electronics under strain: a review of mechanical characterization and durability enhancement strategies," J. Mater. Sci. 51, 2772-2805 (2016).
6 C.-C. Lee, P.-C. Huang, and K.-S. Wang, "Flexural capability of patterned transparent conductive substrate by performing electrical measurements and stress simulations," Materials 9, 850 (2016).   DOI
7 Y. J. Lim, J. H. Yoon, H. S. Yoo, S. M. Song, R. Manda, S. Pagidi, M.-H. Lee, J.-M. Myong, and S. H. Lee, "Fast switchable field-induced optical birefringence in highly transparent polymer-liquid crystal composite," Opt. Mater. Express 8, 3698-3707 (2018).   DOI
8 S. Pagidi, R. Manda, Y. J. Lim, S. M. Song, H. S. Yoo, J. H. Woo, Y.-H. Lin, and S. H. Lee, "Hellical pitch-dependent electro-optics of optically high transparent nano-phase separated liquid crystals," Opt. Express 26, 27368-27380 (2018)   DOI
9 P. Su, G. Vladmir, and S. K. Hoi, "P-155: High-performance coatable polarizer by photoalignment," SID Symposium Digest of Technical Papers 48, 1866-1868 (2017).
10 C. M. Chang, Y. H. Lin, V. Reshetnyak, C. H. Park, R. Manda, and S. H. Lee, "Origins of Kerr phase and orientational phase in polymer-dispersed liquid crystals," Opt. Express 25, 19807-19821 (2017).   DOI
11 A. N. Krasnov, "High-contrast organic light-emitting diodes on flexible substrates," Appl. Phys. Lett. 80, 3853-3855 (2002).   DOI
12 S. K. Park, S. E. Kim, D. Y. Kim, S. W. Kang, S. Shin, S. W. Kuo, S. H. Hwang, S. H Lee, M. H. Lee, and K. U. Jeong, "Polymer-stabilized chromonic liquid-crystalline polarizer," Adv. Funct. Mater. 21, 2129-2139 (2011).   DOI
13 H. Sato, H. Fujikake, Y. Iino, M. Kawakita, and H. Kikuchi, "Flexible grayscale ferroelectric liquid crystal device containing polymer walls and networks," Jpn. J. Appl. Phys. 41, 5302-5306 (2002).   DOI
14 H. Fujikake, H. Sato, and T. Murashige, "Polymer-stabilized ferroelectric liquid crystal for flexible displays," Displays 25, 3-8 (2004).   DOI
15 D.-W. Kim, C.-J. Yu, Y.-W. Lim, J.-H. Na, and S.-D. Lee, "Mechanical stability of a flexible ferroelectric liquid crystal display with a periodic array of columnar spacers," Appl. Phys. Lett. 87, 051017 (2005).
16 Y. Li, L.-W. Tan, X.-T. Hao, K. S. Ong, F. R. Zhu, and L.-S. Hung, "Flexible top-emitting electroluminescent devices on polyethylene terephthalate substrates," Appl. Phys. Lett. 86, 153508 (2005).   DOI
17 M. Choi, B. Jang, W. Lee, S. Lee, T. W. Kim, H. J. Lee, J. H. Kim, and J. H. Ahn, "Stretchable active matrix inorganic light-emitting diode display enabled by overlayaligned roll-transfer printing," Adv. Funct. Mater. 27, 1606005 (2017).   DOI
18 A. K. Srivastava, M. Kim, S. M. Kim, M.-K. Kim, K. Lee, Y. H. Lee, M.-H. Lee, and S. H. Lee, "Dielectrophoretic and electrophoretic force analysis of colloidal fullerenes in a nematic liquid-crystal medium," Phys. Rev. E 80, 051702 (2009).   DOI
19 S. G. Kim, S. M. Kim, Y. S. Kim, H. K. Lee, S. H. Lee, G. D. Lee, J. J. Lyu, and K. H. Kim, "Stabilization of the liquid crystal director in the patterned vertical alignment mode through formation of pretilt angle by reactive mesogen," Appl. Phys. Lett. 90, 261910 (2007).   DOI
20 Y. J. Lim, H. J. Kim, Y. C. Chae, G. Murali, J. H. Lee, B. Mun, D. Y. Gwon, G. Lee, and S. H. Lee, "Fast switching and low operating vertical alignment liquid crystal display with 3-D polymer network for flexible display," IEEE Trans. Electron Devices 64, 1083-1087 (2017).   DOI
21 M. Kim, H. S. Jin, S. J. Lee, Y.-H. Shin, H. G. Ham, D.-K. Yang, P. J. Bos, J. H. Lee, and S. H. Lee, "Liquid crystals for superior electro-optic performance display device with power-saving mode," Adv. Opt. Mater. 6, 1800022 (2018).   DOI
22 M. Ohe and K. Kondo, "Electro-optical characteristics and switching behavior of the in-plane switching mode," Appl. Phys. Lett. 67, 3895-3897 (1995).   DOI
23 S. H. Lee, S. L. Lee, and H. Y. Kim, "Electro-optic characteristics and switching principle of a nematic liquid crystal cell controlled by fringe-field switching," Appl. Phys. Lett. 73, 2881-2883 (1998).   DOI
24 O. Shinichiro, H. Yosuke, J. Lu, Y. Yohei, A. Genki, H. Emi, H. Toshiyuki, and K. Shinichi, "58-1: Invited Paper: High resolution IPS-LCDs fabricated with transparent polyimide substrates," SID Symposium Digest of Technical Papers 49, 764-767 (2018).
25 T. Murashige, H. Fujikake, H. Sato, H. Kikuchi, T. Kurita, and F. Sato, "Polymer wall formation using liquid-crystal/ polymer phase separation induced on patterned polyimide films," Jpn. J. Appl. Phys. 43, L1578-L1580 (2004).   DOI
26 P. Mach, S. J. Rodriguez, R. Nortrup, P. Wiltzius, and J. A. Rogers, "Monolithically integrated, flexible display of polymer-dispersed liquid crystal driven by rubber-stamped organic thin-film transistors," Appl. Phys. Lett. 78, 3592-3594 (2001).   DOI
27 S. Matsumoto, M. Houlbert, T. Hayashi, and K. Kubodera, "Fine droplets of liquid crystals in a transparent polymer and their response to an electric field," Appl. Phys. Lett. 69, 1044-1046 (1996).   DOI