Abstract

A new photoalignment method of controlling the pretilt angle of liquid crystals (LCs) by using organic/inorganic hybrid interpenetrating polymer networks (IPNs) is proposed and demonstrated. In the hybrid IPN alignment layer system, the competition between poly(vinyl cinnamate) (PVCi) favoring planar alignment and poly(dimethyl siloxane) (PDMS) favoring vertical alignment made it possible to achieve pretilt angle in a wide range from 0° to 90°, and adjust pretilt angle as a function of PDMS content. In addition, we achieved the high azimuthal anchoring energy at the intermediate pretilt angle by using PDMS as the vertical-aligning component.

© 2009 OSA

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. K. Takatoh, M. Hasegawa, M. Koden, N. Itoh, R. Hasegawa, and M. Sakamoto, “Applications of nematic liquid crystals” in Alignment Technologies and Applications of Liquid Crystal Devices, G. W. Gray, J. W. Goodby, and A. Fukuda, eds. (Taylor & Francis, 2005), pp. 117–121.
  2. J. L. Janning, “Thin film surface orientation for liquid crystals,” Appl. Phys. Lett. 21(4), 173–174 (1972).
    [CrossRef]
  3. H. Hatoh, K. Shohara, Y. Kinoshita, and N. Ookoshi, “Molecular tilt direction in a slightly tilted homeotropic aligned liquid crystal cell,” Appl. Phys. Lett. 63(26), 3577–3579 (1993).
    [CrossRef]
  4. G. P. Sinha, B. Wen, and C. Rosenblatt, “Large, continuously controllable nematic pretilt from vertical orientation,” Appl. Phys. Lett. 79(16), 2543–2545 (2001).
    [CrossRef]
  5. H. D. Jayathilake, M. H. Zhu, C. Rosenblatt, A. N. Bordenyuk, C. Weeraman, and A. V. Benderskii, “Rubbing-induced anisotropy of long alkyl side chains at polyimide surfaces,” J. Chem. Phys. 125(6), 064706 (2006).
    [CrossRef]
  6. F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
    [CrossRef]
  7. F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
    [CrossRef]
  8. K. E. Vaughn, M. Sousa, D. Kang, and C. Rosenblatt, “Continuous control of liquid crystal pretilt angle from homeotropic to planar,” Appl. Phys. Lett. 90(19), 194102 (2007).
    [CrossRef]
  9. J. Y. Ho, V. G. Chigrinov, and H. S. Kwok, “Variable liquid crystal pretilt angles generated by photoalignment of a mixed polyimide alignment layer,” Appl. Phys. Lett. 90(24), 243506 (2007).
    [CrossRef]
  10. J.-H. Lee, D.-S. Kang, C. M. Clarke, and C. Rosenblatt, “Full control of nematic pretilt angle using spatially homogeneous mixtures of two polyimide alignment materials,” J. Appl. Phys. 105(2), 023508 (2009).
    [CrossRef]
  11. J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, D. C. Hyun, and H. K. Baik, “Variable liquid crystal pretilt angles on various compositions of alignment layers,” Appl. Phys. Lett. 90(4), 043515 (2007).
    [CrossRef]
  12. J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
    [CrossRef]
  13. S. Furumi and K. Ichimura, “Photogeneration of High Pretilt Angles of Nematic Liquid Crystals by Non-Polarized Light Irradiation of Azobenzene-Containing Polymer Films,” Adv. Funct. Mater. 14(3), 247–254 (2004).
    [CrossRef]
  14. B. Zhang, F. K. Lee, O. K. C. Tsui, and P. Sheng, “Liquid crystal orientation transition on microtextured substrates,” Phys. Rev. Lett. 91(21), 215501 (2003).
    [CrossRef] [PubMed]
  15. J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
    [CrossRef]
  16. Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
    [CrossRef]
  17. S.-C. Jeng, S.-J. Hwang, and C.-Y. Yang, “Tunable pretilt angles based on nanoparticles-doped planar liquid-crystal cells,” Opt. Lett. 34(4), 455–457 (2009).
    [CrossRef] [PubMed]
  18. K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Pretilt angle control of liquid crystal molecules by photoaligned films of azobenzene-containing polyimide with a different content of side-chain,” J. Appl. Phys. 104(11), 113528 (2008).
    [CrossRef]
  19. M. Schadt, K. Schmitt, V. Kozinkov, and V. Chigrinov, “Surface-induced parallel alignment of liquid crystals by linearly polymerized photopolymers,” Jpn. J. Appl. Phys. 31(Part 1, No. 7), 2155–2164 (1992).
    [CrossRef]
  20. S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
    [CrossRef]
  21. S. J. Sung, K. Y. Cho, H.-D. Hah, J.-M. Lee, H. K. Shim, and J. K. Park, “Two different reaction mechanisms of cinnamate side groups attached to the various polymer backbones,” Polymer (Guildf.) 47(7), 2314–2321 (2006).
    [CrossRef]
  22. G. C. Meyer, “The influence of stannous octanolate on the polymerization of acrylic compounds,” Makromol. Chem., Rapid. Commun. 4(4), 221–225 (1983).
    [CrossRef]
  23. X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methylmethacrylate) interpenetrating polymer networks: 1. Efficiency of stannous octoate as catalyst in the formation of polydimethylsiloxane networks in methyl methacrylate,” Polymer (Guildf.) 30(2), 364–368 (1989).
    [CrossRef]
  24. X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methyl methacrylate) interpenetrating polymer networks: 2. Synthesis and properties,” Polymer (Guildf.) 33(4), 866–871 (1992).
    [CrossRef]
  25. R. Vendamme, S.-Y. Onoue, A. Nakao, and T. Kunitake, “Robust free-standing nanomembranes of organic/inorganic interpenetrating networks,” Nat. Mater. 5(6), 494–501 (2006).
    [CrossRef] [PubMed]
  26. S. Lee, Y.-C. Jeong, Y. Heo, S. I. Kim, Y.-S. Choi, and J.-K. Park, “Holographic photopolymers of organic/inorganic hybrid interpenetrating networks for reduced volume shrinkage,” J. Mater. Chem. 19(8), 1105–1115 (2009).
    [CrossRef]
  27. Y. W. Li, J. Y. L. Ho, F. S. Y. Yeung, and H. S. Kwok, “Simultaneous determination of large pretilt angles and cell gap in liquid crystal displays,” J. Disp. Technol. 4(1), 13–17 (2008).
    [CrossRef]
  28. X. T. Li, D. H. Pei, S. Kobayashi, and Y. Iimura, “Measurement of Azimuthal Anchoring Energy at Liquid Crystal/Photopolymer Interface,” Jpn. J. Appl. Phys. 36(Part 2, No. 4A), L432–L434 (1997).
    [CrossRef]

2009 (4)

J.-H. Lee, D.-S. Kang, C. M. Clarke, and C. Rosenblatt, “Full control of nematic pretilt angle using spatially homogeneous mixtures of two polyimide alignment materials,” J. Appl. Phys. 105(2), 023508 (2009).
[CrossRef]

Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
[CrossRef]

S.-C. Jeng, S.-J. Hwang, and C.-Y. Yang, “Tunable pretilt angles based on nanoparticles-doped planar liquid-crystal cells,” Opt. Lett. 34(4), 455–457 (2009).
[CrossRef] [PubMed]

S. Lee, Y.-C. Jeong, Y. Heo, S. I. Kim, Y.-S. Choi, and J.-K. Park, “Holographic photopolymers of organic/inorganic hybrid interpenetrating networks for reduced volume shrinkage,” J. Mater. Chem. 19(8), 1105–1115 (2009).
[CrossRef]

2008 (2)

Y. W. Li, J. Y. L. Ho, F. S. Y. Yeung, and H. S. Kwok, “Simultaneous determination of large pretilt angles and cell gap in liquid crystal displays,” J. Disp. Technol. 4(1), 13–17 (2008).
[CrossRef]

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Pretilt angle control of liquid crystal molecules by photoaligned films of azobenzene-containing polyimide with a different content of side-chain,” J. Appl. Phys. 104(11), 113528 (2008).
[CrossRef]

2007 (5)

K. E. Vaughn, M. Sousa, D. Kang, and C. Rosenblatt, “Continuous control of liquid crystal pretilt angle from homeotropic to planar,” Appl. Phys. Lett. 90(19), 194102 (2007).
[CrossRef]

J. Y. Ho, V. G. Chigrinov, and H. S. Kwok, “Variable liquid crystal pretilt angles generated by photoalignment of a mixed polyimide alignment layer,” Appl. Phys. Lett. 90(24), 243506 (2007).
[CrossRef]

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, D. C. Hyun, and H. K. Baik, “Variable liquid crystal pretilt angles on various compositions of alignment layers,” Appl. Phys. Lett. 90(4), 043515 (2007).
[CrossRef]

J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
[CrossRef]

2006 (5)

H. D. Jayathilake, M. H. Zhu, C. Rosenblatt, A. N. Bordenyuk, C. Weeraman, and A. V. Benderskii, “Rubbing-induced anisotropy of long alkyl side chains at polyimide surfaces,” J. Chem. Phys. 125(6), 064706 (2006).
[CrossRef]

F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
[CrossRef]

F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
[CrossRef]

R. Vendamme, S.-Y. Onoue, A. Nakao, and T. Kunitake, “Robust free-standing nanomembranes of organic/inorganic interpenetrating networks,” Nat. Mater. 5(6), 494–501 (2006).
[CrossRef] [PubMed]

S. J. Sung, K. Y. Cho, H.-D. Hah, J.-M. Lee, H. K. Shim, and J. K. Park, “Two different reaction mechanisms of cinnamate side groups attached to the various polymer backbones,” Polymer (Guildf.) 47(7), 2314–2321 (2006).
[CrossRef]

2004 (2)

S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
[CrossRef]

S. Furumi and K. Ichimura, “Photogeneration of High Pretilt Angles of Nematic Liquid Crystals by Non-Polarized Light Irradiation of Azobenzene-Containing Polymer Films,” Adv. Funct. Mater. 14(3), 247–254 (2004).
[CrossRef]

2003 (1)

B. Zhang, F. K. Lee, O. K. C. Tsui, and P. Sheng, “Liquid crystal orientation transition on microtextured substrates,” Phys. Rev. Lett. 91(21), 215501 (2003).
[CrossRef] [PubMed]

2001 (1)

G. P. Sinha, B. Wen, and C. Rosenblatt, “Large, continuously controllable nematic pretilt from vertical orientation,” Appl. Phys. Lett. 79(16), 2543–2545 (2001).
[CrossRef]

1997 (1)

X. T. Li, D. H. Pei, S. Kobayashi, and Y. Iimura, “Measurement of Azimuthal Anchoring Energy at Liquid Crystal/Photopolymer Interface,” Jpn. J. Appl. Phys. 36(Part 2, No. 4A), L432–L434 (1997).
[CrossRef]

1993 (1)

H. Hatoh, K. Shohara, Y. Kinoshita, and N. Ookoshi, “Molecular tilt direction in a slightly tilted homeotropic aligned liquid crystal cell,” Appl. Phys. Lett. 63(26), 3577–3579 (1993).
[CrossRef]

1992 (2)

M. Schadt, K. Schmitt, V. Kozinkov, and V. Chigrinov, “Surface-induced parallel alignment of liquid crystals by linearly polymerized photopolymers,” Jpn. J. Appl. Phys. 31(Part 1, No. 7), 2155–2164 (1992).
[CrossRef]

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methyl methacrylate) interpenetrating polymer networks: 2. Synthesis and properties,” Polymer (Guildf.) 33(4), 866–871 (1992).
[CrossRef]

1989 (1)

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methylmethacrylate) interpenetrating polymer networks: 1. Efficiency of stannous octoate as catalyst in the formation of polydimethylsiloxane networks in methyl methacrylate,” Polymer (Guildf.) 30(2), 364–368 (1989).
[CrossRef]

1983 (1)

G. C. Meyer, “The influence of stannous octanolate on the polymerization of acrylic compounds,” Makromol. Chem., Rapid. Commun. 4(4), 221–225 (1983).
[CrossRef]

1972 (1)

J. L. Janning, “Thin film surface orientation for liquid crystals,” Appl. Phys. Lett. 21(4), 173–174 (1972).
[CrossRef]

Ahn, H. J.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, D. C. Hyun, and H. K. Baik, “Variable liquid crystal pretilt angles on various compositions of alignment layers,” Appl. Phys. Lett. 90(4), 043515 (2007).
[CrossRef]

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

Baik, H. K.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, D. C. Hyun, and H. K. Baik, “Variable liquid crystal pretilt angles on various compositions of alignment layers,” Appl. Phys. Lett. 90(4), 043515 (2007).
[CrossRef]

Benderskii, A. V.

H. D. Jayathilake, M. H. Zhu, C. Rosenblatt, A. N. Bordenyuk, C. Weeraman, and A. V. Benderskii, “Rubbing-induced anisotropy of long alkyl side chains at polyimide surfaces,” J. Chem. Phys. 125(6), 064706 (2006).
[CrossRef]

Bordenyuk, A. N.

H. D. Jayathilake, M. H. Zhu, C. Rosenblatt, A. N. Bordenyuk, C. Weeraman, and A. V. Benderskii, “Rubbing-induced anisotropy of long alkyl side chains at polyimide surfaces,” J. Chem. Phys. 125(6), 064706 (2006).
[CrossRef]

Chang, H. S.

S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
[CrossRef]

Chigrinov, V.

M. Schadt, K. Schmitt, V. Kozinkov, and V. Chigrinov, “Surface-induced parallel alignment of liquid crystals by linearly polymerized photopolymers,” Jpn. J. Appl. Phys. 31(Part 1, No. 7), 2155–2164 (1992).
[CrossRef]

Chigrinov, V. G.

J. Y. Ho, V. G. Chigrinov, and H. S. Kwok, “Variable liquid crystal pretilt angles generated by photoalignment of a mixed polyimide alignment layer,” Appl. Phys. Lett. 90(24), 243506 (2007).
[CrossRef]

Cho, I.-W.

S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
[CrossRef]

Cho, K. Y.

S. J. Sung, K. Y. Cho, H.-D. Hah, J.-M. Lee, H. K. Shim, and J. K. Park, “Two different reaction mechanisms of cinnamate side groups attached to the various polymer backbones,” Polymer (Guildf.) 47(7), 2314–2321 (2006).
[CrossRef]

S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
[CrossRef]

Choi, C. J.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

Choi, Y.-S.

S. Lee, Y.-C. Jeong, Y. Heo, S. I. Kim, Y.-S. Choi, and J.-K. Park, “Holographic photopolymers of organic/inorganic hybrid interpenetrating networks for reduced volume shrinkage,” J. Mater. Chem. 19(8), 1105–1115 (2009).
[CrossRef]

Clarke, C. M.

J.-H. Lee, D.-S. Kang, C. M. Clarke, and C. Rosenblatt, “Full control of nematic pretilt angle using spatially homogeneous mixtures of two polyimide alignment materials,” J. Appl. Phys. 105(2), 023508 (2009).
[CrossRef]

Furumi, S.

S. Furumi and K. Ichimura, “Photogeneration of High Pretilt Angles of Nematic Liquid Crystals by Non-Polarized Light Irradiation of Azobenzene-Containing Polymer Films,” Adv. Funct. Mater. 14(3), 247–254 (2004).
[CrossRef]

Gwag, J. S.

Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
[CrossRef]

Hah, H.-D.

S. J. Sung, K. Y. Cho, H.-D. Hah, J.-M. Lee, H. K. Shim, and J. K. Park, “Two different reaction mechanisms of cinnamate side groups attached to the various polymer backbones,” Polymer (Guildf.) 47(7), 2314–2321 (2006).
[CrossRef]

Hatoh, H.

H. Hatoh, K. Shohara, Y. Kinoshita, and N. Ookoshi, “Molecular tilt direction in a slightly tilted homeotropic aligned liquid crystal cell,” Appl. Phys. Lett. 63(26), 3577–3579 (1993).
[CrossRef]

He, X. W.

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methyl methacrylate) interpenetrating polymer networks: 2. Synthesis and properties,” Polymer (Guildf.) 33(4), 866–871 (1992).
[CrossRef]

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methylmethacrylate) interpenetrating polymer networks: 1. Efficiency of stannous octoate as catalyst in the formation of polydimethylsiloxane networks in methyl methacrylate,” Polymer (Guildf.) 30(2), 364–368 (1989).
[CrossRef]

Heo, Y.

S. Lee, Y.-C. Jeong, Y. Heo, S. I. Kim, Y.-S. Choi, and J.-K. Park, “Holographic photopolymers of organic/inorganic hybrid interpenetrating networks for reduced volume shrinkage,” J. Mater. Chem. 19(8), 1105–1115 (2009).
[CrossRef]

Herz, J. E.

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methyl methacrylate) interpenetrating polymer networks: 2. Synthesis and properties,” Polymer (Guildf.) 33(4), 866–871 (1992).
[CrossRef]

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methylmethacrylate) interpenetrating polymer networks: 1. Efficiency of stannous octoate as catalyst in the formation of polydimethylsiloxane networks in methyl methacrylate,” Polymer (Guildf.) 30(2), 364–368 (1989).
[CrossRef]

Ho, J. Y.

J. Y. Ho, V. G. Chigrinov, and H. S. Kwok, “Variable liquid crystal pretilt angles generated by photoalignment of a mixed polyimide alignment layer,” Appl. Phys. Lett. 90(24), 243506 (2007).
[CrossRef]

F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
[CrossRef]

Ho, J. Y. L.

Y. W. Li, J. Y. L. Ho, F. S. Y. Yeung, and H. S. Kwok, “Simultaneous determination of large pretilt angles and cell gap in liquid crystal displays,” J. Disp. Technol. 4(1), 13–17 (2008).
[CrossRef]

Hwang, B. H.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, D. C. Hyun, and H. K. Baik, “Variable liquid crystal pretilt angles on various compositions of alignment layers,” Appl. Phys. Lett. 90(4), 043515 (2007).
[CrossRef]

Hwang, S.-J.

Hyun, D. C.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, D. C. Hyun, and H. K. Baik, “Variable liquid crystal pretilt angles on various compositions of alignment layers,” Appl. Phys. Lett. 90(4), 043515 (2007).
[CrossRef]

Ichimura, K.

S. Furumi and K. Ichimura, “Photogeneration of High Pretilt Angles of Nematic Liquid Crystals by Non-Polarized Light Irradiation of Azobenzene-Containing Polymer Films,” Adv. Funct. Mater. 14(3), 247–254 (2004).
[CrossRef]

Iimura, Y.

X. T. Li, D. H. Pei, S. Kobayashi, and Y. Iimura, “Measurement of Azimuthal Anchoring Energy at Liquid Crystal/Photopolymer Interface,” Jpn. J. Appl. Phys. 36(Part 2, No. 4A), L432–L434 (1997).
[CrossRef]

Jang, H. J.

J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
[CrossRef]

Janning, J. L.

J. L. Janning, “Thin film surface orientation for liquid crystals,” Appl. Phys. Lett. 21(4), 173–174 (1972).
[CrossRef]

Jayathilake, H. D.

H. D. Jayathilake, M. H. Zhu, C. Rosenblatt, A. N. Bordenyuk, C. Weeraman, and A. V. Benderskii, “Rubbing-induced anisotropy of long alkyl side chains at polyimide surfaces,” J. Chem. Phys. 125(6), 064706 (2006).
[CrossRef]

Jeng, S.-C.

Jeong, Y.-C.

S. Lee, Y.-C. Jeong, Y. Heo, S. I. Kim, Y.-S. Choi, and J.-K. Park, “Holographic photopolymers of organic/inorganic hybrid interpenetrating networks for reduced volume shrinkage,” J. Mater. Chem. 19(8), 1105–1115 (2009).
[CrossRef]

Jo, M. K.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

Jo, S. I.

Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
[CrossRef]

Jo, S. J.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

Kang, D.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

K. E. Vaughn, M. Sousa, D. Kang, and C. Rosenblatt, “Continuous control of liquid crystal pretilt angle from homeotropic to planar,” Appl. Phys. Lett. 90(19), 194102 (2007).
[CrossRef]

Kang, D.-S.

J.-H. Lee, D.-S. Kang, C. M. Clarke, and C. Rosenblatt, “Full control of nematic pretilt angle using spatially homogeneous mixtures of two polyimide alignment materials,” J. Appl. Phys. 105(2), 023508 (2009).
[CrossRef]

Kang, I.-B.

J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
[CrossRef]

Kang, S.-G.

Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
[CrossRef]

Kim, C. S.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

Kim, J. B.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, D. C. Hyun, and H. K. Baik, “Variable liquid crystal pretilt angles on various compositions of alignment layers,” Appl. Phys. Lett. 90(4), 043515 (2007).
[CrossRef]

Kim, J. C.

J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
[CrossRef]

Kim, J. T.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

Kim, J.-H.

Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
[CrossRef]

Kim, K. C.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, D. C. Hyun, and H. K. Baik, “Variable liquid crystal pretilt angles on various compositions of alignment layers,” Appl. Phys. Lett. 90(4), 043515 (2007).
[CrossRef]

Kim, S. I.

S. Lee, Y.-C. Jeong, Y. Heo, S. I. Kim, Y.-S. Choi, and J.-K. Park, “Holographic photopolymers of organic/inorganic hybrid interpenetrating networks for reduced volume shrinkage,” J. Mater. Chem. 19(8), 1105–1115 (2009).
[CrossRef]

Kim, W. S.

S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
[CrossRef]

Kim, Y. S.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

Kim, Y.-K.

Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
[CrossRef]

Kinoshita, Y.

H. Hatoh, K. Shohara, Y. Kinoshita, and N. Ookoshi, “Molecular tilt direction in a slightly tilted homeotropic aligned liquid crystal cell,” Appl. Phys. Lett. 63(26), 3577–3579 (1993).
[CrossRef]

Kobayashi, S.

X. T. Li, D. H. Pei, S. Kobayashi, and Y. Iimura, “Measurement of Azimuthal Anchoring Energy at Liquid Crystal/Photopolymer Interface,” Jpn. J. Appl. Phys. 36(Part 2, No. 4A), L432–L434 (1997).
[CrossRef]

Kozinkov, V.

M. Schadt, K. Schmitt, V. Kozinkov, and V. Chigrinov, “Surface-induced parallel alignment of liquid crystals by linearly polymerized photopolymers,” Jpn. J. Appl. Phys. 31(Part 1, No. 7), 2155–2164 (1992).
[CrossRef]

Kunitake, T.

R. Vendamme, S.-Y. Onoue, A. Nakao, and T. Kunitake, “Robust free-standing nanomembranes of organic/inorganic interpenetrating networks,” Nat. Mater. 5(6), 494–501 (2006).
[CrossRef] [PubMed]

Kwok, H. S.

Y. W. Li, J. Y. L. Ho, F. S. Y. Yeung, and H. S. Kwok, “Simultaneous determination of large pretilt angles and cell gap in liquid crystal displays,” J. Disp. Technol. 4(1), 13–17 (2008).
[CrossRef]

J. Y. Ho, V. G. Chigrinov, and H. S. Kwok, “Variable liquid crystal pretilt angles generated by photoalignment of a mixed polyimide alignment layer,” Appl. Phys. Lett. 90(24), 243506 (2007).
[CrossRef]

F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
[CrossRef]

Kwok, H.-S.

F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
[CrossRef]

Lee, F. K.

F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
[CrossRef]

B. Zhang, F. K. Lee, O. K. C. Tsui, and P. Sheng, “Liquid crystal orientation transition on microtextured substrates,” Phys. Rev. Lett. 91(21), 215501 (2003).
[CrossRef] [PubMed]

Lee, J.-H.

J.-H. Lee, D.-S. Kang, C. M. Clarke, and C. Rosenblatt, “Full control of nematic pretilt angle using spatially homogeneous mixtures of two polyimide alignment materials,” J. Appl. Phys. 105(2), 023508 (2009).
[CrossRef]

Lee, J.-M.

S. J. Sung, K. Y. Cho, H.-D. Hah, J.-M. Lee, H. K. Shim, and J. K. Park, “Two different reaction mechanisms of cinnamate side groups attached to the various polymer backbones,” Polymer (Guildf.) 47(7), 2314–2321 (2006).
[CrossRef]

Lee, S.

S. Lee, Y.-C. Jeong, Y. Heo, S. I. Kim, Y.-S. Choi, and J.-K. Park, “Holographic photopolymers of organic/inorganic hybrid interpenetrating networks for reduced volume shrinkage,” J. Mater. Chem. 19(8), 1105–1115 (2009).
[CrossRef]

Lee, S. R.

J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
[CrossRef]

Lee, Y.-J.

Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
[CrossRef]

Li, X. T.

X. T. Li, D. H. Pei, S. Kobayashi, and Y. Iimura, “Measurement of Azimuthal Anchoring Energy at Liquid Crystal/Photopolymer Interface,” Jpn. J. Appl. Phys. 36(Part 2, No. 4A), L432–L434 (1997).
[CrossRef]

Li, Y. W.

Y. W. Li, J. Y. L. Ho, F. S. Y. Yeung, and H. S. Kwok, “Simultaneous determination of large pretilt angles and cell gap in liquid crystal displays,” J. Disp. Technol. 4(1), 13–17 (2008).
[CrossRef]

F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
[CrossRef]

Meyer, G. C.

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methyl methacrylate) interpenetrating polymer networks: 2. Synthesis and properties,” Polymer (Guildf.) 33(4), 866–871 (1992).
[CrossRef]

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methylmethacrylate) interpenetrating polymer networks: 1. Efficiency of stannous octoate as catalyst in the formation of polydimethylsiloxane networks in methyl methacrylate,” Polymer (Guildf.) 30(2), 364–368 (1989).
[CrossRef]

G. C. Meyer, “The influence of stannous octanolate on the polymerization of acrylic compounds,” Makromol. Chem., Rapid. Commun. 4(4), 221–225 (1983).
[CrossRef]

Nakao, A.

R. Vendamme, S.-Y. Onoue, A. Nakao, and T. Kunitake, “Robust free-standing nanomembranes of organic/inorganic interpenetrating networks,” Nat. Mater. 5(6), 494–501 (2006).
[CrossRef] [PubMed]

Oh, C. H.

J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
[CrossRef]

Onoue, S.-Y.

R. Vendamme, S.-Y. Onoue, A. Nakao, and T. Kunitake, “Robust free-standing nanomembranes of organic/inorganic interpenetrating networks,” Nat. Mater. 5(6), 494–501 (2006).
[CrossRef] [PubMed]

Ookoshi, N.

H. Hatoh, K. Shohara, Y. Kinoshita, and N. Ookoshi, “Molecular tilt direction in a slightly tilted homeotropic aligned liquid crystal cell,” Appl. Phys. Lett. 63(26), 3577–3579 (1993).
[CrossRef]

Park, J. K.

S. J. Sung, K. Y. Cho, H.-D. Hah, J.-M. Lee, H. K. Shim, and J. K. Park, “Two different reaction mechanisms of cinnamate side groups attached to the various polymer backbones,” Polymer (Guildf.) 47(7), 2314–2321 (2006).
[CrossRef]

S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
[CrossRef]

Park, J. S.

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

Park, J.-K.

S. Lee, Y.-C. Jeong, Y. Heo, S. I. Kim, Y.-S. Choi, and J.-K. Park, “Holographic photopolymers of organic/inorganic hybrid interpenetrating networks for reduced volume shrinkage,” J. Mater. Chem. 19(8), 1105–1115 (2009).
[CrossRef]

Park, Y. R.

Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
[CrossRef]

Pei, D. H.

X. T. Li, D. H. Pei, S. Kobayashi, and Y. Iimura, “Measurement of Azimuthal Anchoring Energy at Liquid Crystal/Photopolymer Interface,” Jpn. J. Appl. Phys. 36(Part 2, No. 4A), L432–L434 (1997).
[CrossRef]

Rosenblatt, C.

J.-H. Lee, D.-S. Kang, C. M. Clarke, and C. Rosenblatt, “Full control of nematic pretilt angle using spatially homogeneous mixtures of two polyimide alignment materials,” J. Appl. Phys. 105(2), 023508 (2009).
[CrossRef]

K. E. Vaughn, M. Sousa, D. Kang, and C. Rosenblatt, “Continuous control of liquid crystal pretilt angle from homeotropic to planar,” Appl. Phys. Lett. 90(19), 194102 (2007).
[CrossRef]

H. D. Jayathilake, M. H. Zhu, C. Rosenblatt, A. N. Bordenyuk, C. Weeraman, and A. V. Benderskii, “Rubbing-induced anisotropy of long alkyl side chains at polyimide surfaces,” J. Chem. Phys. 125(6), 064706 (2006).
[CrossRef]

G. P. Sinha, B. Wen, and C. Rosenblatt, “Large, continuously controllable nematic pretilt from vertical orientation,” Appl. Phys. Lett. 79(16), 2543–2545 (2001).
[CrossRef]

Sakamoto, K.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Pretilt angle control of liquid crystal molecules by photoaligned films of azobenzene-containing polyimide with a different content of side-chain,” J. Appl. Phys. 104(11), 113528 (2008).
[CrossRef]

Schadt, M.

M. Schadt, K. Schmitt, V. Kozinkov, and V. Chigrinov, “Surface-induced parallel alignment of liquid crystals by linearly polymerized photopolymers,” Jpn. J. Appl. Phys. 31(Part 1, No. 7), 2155–2164 (1992).
[CrossRef]

Schmitt, K.

M. Schadt, K. Schmitt, V. Kozinkov, and V. Chigrinov, “Surface-induced parallel alignment of liquid crystals by linearly polymerized photopolymers,” Jpn. J. Appl. Phys. 31(Part 1, No. 7), 2155–2164 (1992).
[CrossRef]

Seo, J.-H.

J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
[CrossRef]

Sheng, P.

F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
[CrossRef]

F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
[CrossRef]

B. Zhang, F. K. Lee, O. K. C. Tsui, and P. Sheng, “Liquid crystal orientation transition on microtextured substrates,” Phys. Rev. Lett. 91(21), 215501 (2003).
[CrossRef] [PubMed]

Shim, H. K.

S. J. Sung, K. Y. Cho, H.-D. Hah, J.-M. Lee, H. K. Shim, and J. K. Park, “Two different reaction mechanisms of cinnamate side groups attached to the various polymer backbones,” Polymer (Guildf.) 47(7), 2314–2321 (2006).
[CrossRef]

Shohara, K.

H. Hatoh, K. Shohara, Y. Kinoshita, and N. Ookoshi, “Molecular tilt direction in a slightly tilted homeotropic aligned liquid crystal cell,” Appl. Phys. Lett. 63(26), 3577–3579 (1993).
[CrossRef]

Sinha, G. P.

G. P. Sinha, B. Wen, and C. Rosenblatt, “Large, continuously controllable nematic pretilt from vertical orientation,” Appl. Phys. Lett. 79(16), 2543–2545 (2001).
[CrossRef]

Sousa, M.

K. E. Vaughn, M. Sousa, D. Kang, and C. Rosenblatt, “Continuous control of liquid crystal pretilt angle from homeotropic to planar,” Appl. Phys. Lett. 90(19), 194102 (2007).
[CrossRef]

Sung, S. J.

S. J. Sung, K. Y. Cho, H.-D. Hah, J.-M. Lee, H. K. Shim, and J. K. Park, “Two different reaction mechanisms of cinnamate side groups attached to the various polymer backbones,” Polymer (Guildf.) 47(7), 2314–2321 (2006).
[CrossRef]

S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
[CrossRef]

Tsui, O. K.

F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
[CrossRef]

F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
[CrossRef]

Tsui, O. K. C.

B. Zhang, F. K. Lee, O. K. C. Tsui, and P. Sheng, “Liquid crystal orientation transition on microtextured substrates,” Phys. Rev. Lett. 91(21), 215501 (2003).
[CrossRef] [PubMed]

Uehara, Y.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Pretilt angle control of liquid crystal molecules by photoaligned films of azobenzene-containing polyimide with a different content of side-chain,” J. Appl. Phys. 104(11), 113528 (2008).
[CrossRef]

Usami, K.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Pretilt angle control of liquid crystal molecules by photoaligned films of azobenzene-containing polyimide with a different content of side-chain,” J. Appl. Phys. 104(11), 113528 (2008).
[CrossRef]

Ushioda, S.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Pretilt angle control of liquid crystal molecules by photoaligned films of azobenzene-containing polyimide with a different content of side-chain,” J. Appl. Phys. 104(11), 113528 (2008).
[CrossRef]

Vaughn, K. E.

K. E. Vaughn, M. Sousa, D. Kang, and C. Rosenblatt, “Continuous control of liquid crystal pretilt angle from homeotropic to planar,” Appl. Phys. Lett. 90(19), 194102 (2007).
[CrossRef]

Vendamme, R.

R. Vendamme, S.-Y. Onoue, A. Nakao, and T. Kunitake, “Robust free-standing nanomembranes of organic/inorganic interpenetrating networks,” Nat. Mater. 5(6), 494–501 (2006).
[CrossRef] [PubMed]

Wan, J. T.

F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
[CrossRef]

Weeraman, C.

H. D. Jayathilake, M. H. Zhu, C. Rosenblatt, A. N. Bordenyuk, C. Weeraman, and A. V. Benderskii, “Rubbing-induced anisotropy of long alkyl side chains at polyimide surfaces,” J. Chem. Phys. 125(6), 064706 (2006).
[CrossRef]

Wen, B.

G. P. Sinha, B. Wen, and C. Rosenblatt, “Large, continuously controllable nematic pretilt from vertical orientation,” Appl. Phys. Lett. 79(16), 2543–2545 (2001).
[CrossRef]

Widmaier, J. M.

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methyl methacrylate) interpenetrating polymer networks: 2. Synthesis and properties,” Polymer (Guildf.) 33(4), 866–871 (1992).
[CrossRef]

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methylmethacrylate) interpenetrating polymer networks: 1. Efficiency of stannous octoate as catalyst in the formation of polydimethylsiloxane networks in methyl methacrylate,” Polymer (Guildf.) 30(2), 364–368 (1989).
[CrossRef]

Xie, F. C.

F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
[CrossRef]

F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
[CrossRef]

Yang, C.-Y.

Yeung, F. S.

F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
[CrossRef]

F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
[CrossRef]

Yeung, F. S. Y.

Y. W. Li, J. Y. L. Ho, F. S. Y. Yeung, and H. S. Kwok, “Simultaneous determination of large pretilt angles and cell gap in liquid crystal displays,” J. Disp. Technol. 4(1), 13–17 (2008).
[CrossRef]

Yokota, J.

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Pretilt angle control of liquid crystal molecules by photoaligned films of azobenzene-containing polyimide with a different content of side-chain,” J. Appl. Phys. 104(11), 113528 (2008).
[CrossRef]

Yoo, J. H.

S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
[CrossRef]

Yoon, T.-H.

J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
[CrossRef]

Zhang, B.

B. Zhang, F. K. Lee, O. K. C. Tsui, and P. Sheng, “Liquid crystal orientation transition on microtextured substrates,” Phys. Rev. Lett. 91(21), 215501 (2003).
[CrossRef] [PubMed]

Zhu, M. H.

H. D. Jayathilake, M. H. Zhu, C. Rosenblatt, A. N. Bordenyuk, C. Weeraman, and A. V. Benderskii, “Rubbing-induced anisotropy of long alkyl side chains at polyimide surfaces,” J. Chem. Phys. 125(6), 064706 (2006).
[CrossRef]

Adv. Funct. Mater. (1)

S. Furumi and K. Ichimura, “Photogeneration of High Pretilt Angles of Nematic Liquid Crystals by Non-Polarized Light Irradiation of Azobenzene-Containing Polymer Films,” Adv. Funct. Mater. 14(3), 247–254 (2004).
[CrossRef]

Appl. Phys. Lett. (9)

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, D. C. Hyun, and H. K. Baik, “Variable liquid crystal pretilt angles on various compositions of alignment layers,” Appl. Phys. Lett. 90(4), 043515 (2007).
[CrossRef]

J. B. Kim, K. C. Kim, H. J. Ahn, B. H. Hwang, J. T. Kim, S. J. Jo, C. S. Kim, H. K. Baik, C. J. Choi, M. K. Jo, Y. S. Kim, J. S. Park, and D. Kang, “No bias pi cell using a dual alignment layer with an intermediate pretilt angle,” Appl. Phys. Lett. 91(2), 023507 (2007).
[CrossRef]

Y.-J. Lee, J. S. Gwag, Y.-K. Kim, S. I. Jo, S.-G. Kang, Y. R. Park, and J.-H. Kim, “Control of liquid crystal pretilt angle by anchoring competition of the stacked alignment layers,” Appl. Phys. Lett. 94(4), 041113 (2009).
[CrossRef]

J. L. Janning, “Thin film surface orientation for liquid crystals,” Appl. Phys. Lett. 21(4), 173–174 (1972).
[CrossRef]

H. Hatoh, K. Shohara, Y. Kinoshita, and N. Ookoshi, “Molecular tilt direction in a slightly tilted homeotropic aligned liquid crystal cell,” Appl. Phys. Lett. 63(26), 3577–3579 (1993).
[CrossRef]

G. P. Sinha, B. Wen, and C. Rosenblatt, “Large, continuously controllable nematic pretilt from vertical orientation,” Appl. Phys. Lett. 79(16), 2543–2545 (2001).
[CrossRef]

F. S. Yeung, J. Y. Ho, Y. W. Li, F. C. Xie, O. K. Tsui, P. Sheng, and H. S. Kwok, “Variable liquid crystal pretilt angles by nanostructured surfaces,” Appl. Phys. Lett. 88(5), 051910 (2006).
[CrossRef]

K. E. Vaughn, M. Sousa, D. Kang, and C. Rosenblatt, “Continuous control of liquid crystal pretilt angle from homeotropic to planar,” Appl. Phys. Lett. 90(19), 194102 (2007).
[CrossRef]

J. Y. Ho, V. G. Chigrinov, and H. S. Kwok, “Variable liquid crystal pretilt angles generated by photoalignment of a mixed polyimide alignment layer,” Appl. Phys. Lett. 90(24), 243506 (2007).
[CrossRef]

Chem. Phys. Lett. (1)

S. J. Sung, K. Y. Cho, J. H. Yoo, W. S. Kim, H. S. Chang, I.-W. Cho, and J. K. Park, “Dimerization behavior of cinnamate group attached to flexible polymer backbone and its effect on the molecular orientation,” Chem. Phys. Lett. 394(4–6), 238–243 (2004).
[CrossRef]

J. Appl. Phys. (3)

J.-H. Lee, D.-S. Kang, C. M. Clarke, and C. Rosenblatt, “Full control of nematic pretilt angle using spatially homogeneous mixtures of two polyimide alignment materials,” J. Appl. Phys. 105(2), 023508 (2009).
[CrossRef]

F. S. Yeung, F. C. Xie, J. T. Wan, F. K. Lee, O. K. Tsui, P. Sheng, and H.-S. Kwok, “Liquid crystal pretilt angle control using nanotextured surfaces,” J. Appl. Phys. 99(12), 124506 (2006).
[CrossRef]

K. Usami, K. Sakamoto, J. Yokota, Y. Uehara, and S. Ushioda, “Pretilt angle control of liquid crystal molecules by photoaligned films of azobenzene-containing polyimide with a different content of side-chain,” J. Appl. Phys. 104(11), 113528 (2008).
[CrossRef]

J. Chem. Phys. (1)

H. D. Jayathilake, M. H. Zhu, C. Rosenblatt, A. N. Bordenyuk, C. Weeraman, and A. V. Benderskii, “Rubbing-induced anisotropy of long alkyl side chains at polyimide surfaces,” J. Chem. Phys. 125(6), 064706 (2006).
[CrossRef]

J. Disp. Technol. (1)

Y. W. Li, J. Y. L. Ho, F. S. Y. Yeung, and H. S. Kwok, “Simultaneous determination of large pretilt angles and cell gap in liquid crystal displays,” J. Disp. Technol. 4(1), 13–17 (2008).
[CrossRef]

J. Mater. Chem. (1)

S. Lee, Y.-C. Jeong, Y. Heo, S. I. Kim, Y.-S. Choi, and J.-K. Park, “Holographic photopolymers of organic/inorganic hybrid interpenetrating networks for reduced volume shrinkage,” J. Mater. Chem. 19(8), 1105–1115 (2009).
[CrossRef]

Jpn. J. Appl. Phys. (3)

X. T. Li, D. H. Pei, S. Kobayashi, and Y. Iimura, “Measurement of Azimuthal Anchoring Energy at Liquid Crystal/Photopolymer Interface,” Jpn. J. Appl. Phys. 36(Part 2, No. 4A), L432–L434 (1997).
[CrossRef]

M. Schadt, K. Schmitt, V. Kozinkov, and V. Chigrinov, “Surface-induced parallel alignment of liquid crystals by linearly polymerized photopolymers,” Jpn. J. Appl. Phys. 31(Part 1, No. 7), 2155–2164 (1992).
[CrossRef]

J.-H. Seo, H. J. Jang, S. R. Lee, T.-H. Yoon, J. C. Kim, I.-B. Kang, and C. H. Oh, “Wide Pretilt Angle Control of Liquid Crystal Display Device by Ion Beam Exposure on the Vertical Aligning Layer,” Jpn. J. Appl. Phys. 46, L1074–L1076 (2007).
[CrossRef]

Makromol. Chem., Rapid. Commun. (1)

G. C. Meyer, “The influence of stannous octanolate on the polymerization of acrylic compounds,” Makromol. Chem., Rapid. Commun. 4(4), 221–225 (1983).
[CrossRef]

Nat. Mater. (1)

R. Vendamme, S.-Y. Onoue, A. Nakao, and T. Kunitake, “Robust free-standing nanomembranes of organic/inorganic interpenetrating networks,” Nat. Mater. 5(6), 494–501 (2006).
[CrossRef] [PubMed]

Opt. Lett. (1)

Phys. Rev. Lett. (1)

B. Zhang, F. K. Lee, O. K. C. Tsui, and P. Sheng, “Liquid crystal orientation transition on microtextured substrates,” Phys. Rev. Lett. 91(21), 215501 (2003).
[CrossRef] [PubMed]

Polymer (Guildf.) (3)

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methylmethacrylate) interpenetrating polymer networks: 1. Efficiency of stannous octoate as catalyst in the formation of polydimethylsiloxane networks in methyl methacrylate,” Polymer (Guildf.) 30(2), 364–368 (1989).
[CrossRef]

X. W. He, J. M. Widmaier, J. E. Herz, and G. C. Meyer, “Polydimethylsiloxane/poly(methyl methacrylate) interpenetrating polymer networks: 2. Synthesis and properties,” Polymer (Guildf.) 33(4), 866–871 (1992).
[CrossRef]

S. J. Sung, K. Y. Cho, H.-D. Hah, J.-M. Lee, H. K. Shim, and J. K. Park, “Two different reaction mechanisms of cinnamate side groups attached to the various polymer backbones,” Polymer (Guildf.) 47(7), 2314–2321 (2006).
[CrossRef]

Other (1)

K. Takatoh, M. Hasegawa, M. Koden, N. Itoh, R. Hasegawa, and M. Sakamoto, “Applications of nematic liquid crystals” in Alignment Technologies and Applications of Liquid Crystal Devices, G. W. Gray, J. W. Goodby, and A. Fukuda, eds. (Taylor & Francis, 2005), pp. 117–121.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (7)

Fig. 1
Fig. 1

Chemical structures of the hybrid organic/inorganic IPN alignment layer constituents.

Fig. 2
Fig. 2

Schematic for the formation of organic/inorganic hybrid IPNs. (a) Under room temperature, the inorganic clusters were formed by sol-gel reaction between the hydroxyl group of h-PDMS and methoxy group of TMSPM. (b) After formation of inorganic clusters within the matrix precursors, radical polymerization initiated by thermal decomposition of AIBN. During radical polymerization, chemically crosslinked PVCi is generated and tied to inorganic clusters to make a graft-IPN structure. (c) Model structure of the hybrid organic/inorganic IPN. The inorganic clusters are not necessarily connected but rather dispersed in the organic networks. The organic networks are represented in black and the inorganic clusters are represented in blue. (d) Photograph of hybrid IPN alignment layer showing high transparency.

Fig. 3
Fig. 3

(a) Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra of the hybrid IPN alignment layer. (b) Enlarged spectra of Fig. 3a. IR band at 1774 cm−1 correspond to carbonyl (C = O) stretch vibration. The absorption bands at 1261 cm−1 and 802 cm−1 indicates Si-CH3 group and IR bands at 1087 cm−1 and 1018 cm−1 correspond to Si-O-Si stretch vibration.

Fig. 4
Fig. 4

Transmission electron microscope (TEM) images of hybrid IPN alignment layer of (a) IPN2 and (b) IPN20. Energy dispersive X-ray (EDX) analysis results of IPN20 with (c) dark area and (d) bright area.

Fig. 5
Fig. 5

Water contact angles of the surface of the hybrid IPN alignment layer versus PDMS weight proportion. Insets are profiles of water drops on the surface of the hybrid IPN alignment layer

Fig. 6
Fig. 6

Pretilt angles as a function of content of embedded PDMS.

Fig. 7
Fig. 7

Measured azimuthal anchoring energies as a function of PDMS content. Insets are polarized optical microscopic images showing LC alignment at different PDMS content.

Tables (2)

Tables Icon

Table 1 Compositions of the hybrid IPN alignment layer formulations.

Tables Icon

Table 2 Light transmission (%) of the hybrid IPN alignment layer. The wavelength of incident light is 633nm and sample thickness is 75 μm.

Metrics