Ways of increasing the response rate of electrically controlled optical devices based on nematic liquid crystals
L. P. Amosova, V. N. Vasil'ev, N. L. Ivanova, and E. A. Konshina
This review is devoted to the problem of increasing the response rate of liquid-crystal (LC) devices based on nematic liquid crystals (NLCs), such as optical switches, modulators, adjustable attenuators, and stabilizers for the near-IR region. Along with well-known methods such as the regime in which devices operate with displacement and dual-frequency addressing of NLCs with sign inversion of the dielectric anisotropy, which makes it possible to control the relaxation process, the possibility of accelerating the operation by using polymer-dispersed and polymer-stabilized LC mixtures is considered. It is shown to be necessary to optimize the supply regimes of the LC devices. The dynamic responses of devices that use the electrooptic S and twist effects are compared. The prospects of using NLC devices as active components of optical-fiber networks are considered.
ЛИТЕРАТУРА
1. Mao C., Xu M., Feng W., Hyang T., Wu K., Lia J. Liquid-crystal applications in optical telecommunication // Proc. SPIE. 2003. V. 5003. P. 121–129.
2. Liang X., Lu Y.Q., Wu Y.H., Du F., Wang H.Y., Wu S.T. Dual-frequency addressed variable optical attenuator with submillisecond response time // Jap. J. of Appl. Phys. 2005. V. 44. № 3. P. 1292–1295.
3. Hanson E.G. Polarization independent liquid crystal optical attenuator for fiber-optics applications // Appl. Opt. 1982. V. 21. № 7. P. 1342–1344.
4. Wu Y.H., Lin Y.H., Lu Y.Q., Fan Y.H., Wu J.R., Wu S.T. Submillisecond response variable optical attenuator based on sheared polymer network liquid crystal // Optics Express. 2004. V. 12. № 25. P. 6382–6389.
5. Blinov L.M., Chigrinov V.G. Electrooptic effects in liquid crystal materials. New York: Springer, 1994. 464 p.
6. Wu S.T., Efron U. Optical properties of thin nematic liquid crystal cells// Appl. Phys. Lett. 1986. V. 48. № 10. P. 624–626.
7. Wu S.T., Efron U., Lackner A.M. Optimal operation temperature of liquid crystal modulators // Appl. Opt. 1987. V. 26. P. 3441–3445.
8. Wu S.T., Wu C.S. High-speed liquid crystal modulators using transient nematic effect // J. Appl. Phys. 1989. V. 65. № 2. P. 527–532.
9. Березин П.Д., Блинов Л.М., Компанец И.Н., Никитин В.В. Электрооптическое переключение в ориентированных пленках жидкого кристалла // Квант. электрон. 1973. № 1 (13). С. 127–130.
10. Wu S.T., Wu C.S. Small angle relaxation of highly deformed nematic liquid crystals // Appl. Phys. Lett 1988. V. 53. № 19. P. 1794–1796.
11. Wu S.T. Nematic liquid crystal modulator with response time less than 100 μs at room temperature // Appl. Phys. Lett. 1990. V. 57. № 10. P. 986– 988.
12. Fan Y.H., Lin Y.H., Ren. H., Gauza S.,Wu S.T. Fast response and scattering free polymer network liquid crystals for infrared light modulators // Appl. Phys. Lett. 2004. V. 84. № 8. P. 1233–1235.
13. Pain F., Coquille R., Vinouze B., Wolffer N. Comparison of twisted and parallel nematic liquid crystal polarization controllers. Application to a 4Ч4 free space optical switch at 1,5 μm // Opt. Comm. 1997. V. 139. P. 199–204.
14. Lu Y.Q., Du F., Lin Y.H., Wu S.T. Variable optical attenuator based on polуmer-stabilized twisted nematic liquid crystal //Optics Express. 2004. V. 12. № 7. P. 1221–1227.
15. West J.L., Zang G., Glushchenko A., Reznikov Yu. Fast birefringent mode stressed liquid crystal // Appl. Phys. Lett. 2005. V. 86. № 3. P. 031111-1-3.
16. Golovin A.B., Shiyanovskii S.V., Lavrentovich O.D. Fast switching dual-frequency liquid crystal optical retarder, driven by an amplitude and frequency modulated voltage // Appl. Phys. Lett. 2003. V. 83. № 19. P. 3864–3866
17. Brimicombe P.D., Parry-Jones L.A., Elston S.J., Raynes E.P. Modeling of dual frequency liquid crystal materials and devices // J. Appl. Phys. 2005. V. 98. P. 104104-1-6.
18. Коншина Е.А., Федоров М.А., Амосова Л.П., Исаев М.В., Костомаров Д.С. Динамика спада оптического пропускания в ячейках с двухчастотным нематическим жидким кристаллом // Письма в ЖТФ. 2008. Т. 34. В. 9. С. 87–94.
19. Wang H., Wu T.X., Xinyu Z.X., Wu S.T. Correlation between liquid crystal director reorientation and optical response time of a homeotropic cell // J. of Appl. Phys. 2004. V. 95. № 10. P. 5502–5507.
20. Kubono A., Kyokane Y., Akiyama R., Tanaka K. Effects of cell parameters on the properties of hybrid twisted nematic displays // J. of Appl. Phys. 2001. V. 90. № 12. P. 5859–5865.
21. Mottram N.J., Brown C.V. Pulsed addressing of a dual frequency nematic liquid crystal // Phys. Rev. E. V. 74. 2006. P. 031703-1-7.
22. Lu Y.Q., Liang X., Wu Y.-H., Du F., Wang H.Y., Wu S.-T. Dual-frequency addressed hybrid aligned nematic liquid crystal // Appl. Phys. Lett. 2004. V. 85. № 16. P. 3354–3356.
23. Hyang Y., Wen C.H., Wu S.T. Polarization-independent and submillisecond response phase modulators using a 90° twisted dual-frequency liquid crystal // Appl. Phys. Lett. 2006. V. 89. № 2. P. 021103-1-3.
24. Golovin A.B., Pishnyak O.P., Shiyanovskii S.V., Lavrentovich O.D. Achromatic Linear Polarization Switch for Visible and Near Infrared Radiation Based on Dual- Frequency Twisted Nematic Cell // Proc. SPIE. 2006. V. 6135. 61350E. 8 pages.
25. Коншина Е.А., Федоров М.А., Рыбникова А.Е., Амосова Л.П., Иванова Н.Л., Исаев М.В., Костомаров Д.С. Динамика твист-эффекта в двухчастотном нематическом жидком кристалле // ЖТФ. 2009. Т. 79. В. 4. С. 111–116.
26. Коншина Е.А., Федоров М.А., Амосова Л.П., Исаев М.В., Костомаров Д.С. Оптические модуляторы на основе двухчастотного нематического жидкого кристалла // Оптический журнал. 2008. Т. 75. № 10. С. 73–80.
27. Meizi Jiao, Zhibing Ge, Qiong Song, Shin-Tson Wu. Alignment layer effects on thin liquid crystal cells // Appl. Phys. Lett. 2008. V. 92. 061102-1-3.
28. Васильев В.Н., Коншина Е.А., Костомаров Д.С., Федоров М.А., Амосова Л.П., Гавриш Е.О. Влияние ориентирующей поверхности и толщины слоя жидкого кристалла на характеристики электроуправляемых оптических модуляторов // Письма в ЖТФ. 2009. Т. 79. В. 11. С. 111–116.
29. Barber B., Giles C.R., Askyuk V., Ruel R., Stuls L., Bishop D.A. Fiber Connectorized MEMS Variable Optical Attenuator // IEEE Photonics Technology Letters. 1998. V. 10. № 9. P. 1262–1264.
30. Cai H., Zhang X.M., Lu C., Liu A.Q.,Khoo E.H. Linear MEMS Variable Optical Attenuator Using Reflective Elliptical Mirror // IEEE Photonics Technology Letters. 2005. V. 16. № 2. P. 402–404.
31. Chen C., Lee C., Yeh J.A. Retro Reflection Type MOEMS VOA // IEEE Photonics Technology Letters. 2004. V. 16. № 10. P. 2290–2292.
32. Bashir A., Katila P., Ogier N., Saadany B., Khalil D.A. A MEMS- Based VOA with Very Low PDL // IEEE Photonics Technology Letters. 2004. V. 16. № 4. P. 1047–1049.
33. Masafumi I., Akira S., Yasusshi H., Atsushi R., Kouzou T., Atsushi S. A Pixelized VOA Using LC on Silicon Technologyfor Tunable Filters.// Opt. Rev. 2004. V. 11. № 2. P. 132–139.
34. Wu Y.H., Liang X., Lu Y.Q., Du F., Lin Y.H., Wu S.T. Variable optical attenuator with a polуmer-stabilized dual-frequency liquid crystal. // Appl. Opt. 2005. V. 44. № 20. P. 4394–4397.
ПОЛНЫЙ ТЕКСТ
