一种液晶光开关的制备研究
|
摘要
提出了一种新型的液晶光开关器件,它采用全息技术,由向列相液晶和高分子预聚物充分混合,在一定条件下发生定域光聚合反应形成,理论和实验表明,采用一定的材料配方和工艺,才能获得理想的光开关器件。此种器件具有显著的电控开关特性,由于液晶材料的介入,使得器件的折射率调制度可以通过外加电场进行改变,从而其输出光也会随着电场的改变而改变,当电场大于10V时,出射光只有入射光的5%。同时,由于液晶具有大的电光系数、快的响应速度等优点,使得液晶光开关器件在光通信技术中的有非常好的应用前景。
A novel liquid crystal optical switching device is investigated in this paper. Utilizing holographic technique, photosensitive monomers and nematic liquid crystal are mixed together and the phase separation between monomers and liquid crystals was induced by laser beam interference bright patterns and form grating device. According to optical theories and through many experiments, the ideal optical switching device can be obtained when the photosensitive monomers are mixed together with nematic liquid crystal with certain weight ratio. The emergent light intensity of liquid crystal grating can be modulated by electric field because of the electric control characteristics of liquid crystal. The output light is only 5% of the incident light when the electric field is more than 10 V. Besides, the liquid crystal also has the advantages of large electro- optic coefficient and fast response speed. Consequently, the liquid crystal grating has immense potential productivity in passive optical communication device such as optical switching and variable optical attenuator.
A novel liquid crystal optical switching device is investigated in this paper. Utilizing holographic technique, photosensitive monomers and nematic liquid crystal are mixed together and the phase separation between monomers and liquid crystals was induced by laser beam interference bright patterns and form grating device. According to optical theories and through many experiments, the ideal optical switching device can be obtained when the photosensitive monomers are mixed together with nematic liquid crystal with certain weight ratio. The emergent light intensity of liquid crystal grating can be modulated by electric field because of the electric control characteristics of liquid crystal. The output light is only 5% of the incident light when the electric field is more than 10 V. Besides, the liquid crystal also has the advantages of large electro- optic coefficient and fast response speed. Consequently, the liquid crystal grating has immense potential productivity in passive optical communication device such as optical switching and variable optical attenuator.
引文
[1]Natarajan L V,Sutherland R L,Tondiglia V P,et al.Electrically switchable volume gratings in polymer-dispersed liquid crystals[J].Appl.Phys.Lett,1994,64:1074.
[2]Tanaka K,Kato K,Date M.Fabrication of holographic polymer dispersed liquid crystal(HPDLC)with high reflection efficiency[J].Jpn.J.Appl.Phys,1999,38:277-278.
[3]Keiji Tanaka,Kinya Kato,Shinji Tsuru,et al.Holographically formed liquid crystal/polymer device for reflective color display[J].SID’94 Digest,1994,25:37-40.
[4]Veltri A,Caputo R,Umeton C,et al.Model for the photoinduced formation of diffraction gratings in liquid-crystalline composite materials[J].Appl.Phys.Lett,2004,84:3492-3494.
[5]李文萃,郑致刚,刘永刚,等.表面混合排列取向对全息聚合物分散液晶光栅电光特性的影响[J].光学精密工程,2010,18:1504.
[6]Natarajan L V,Sutherland R L,Tondiglia V P,et al.Electrically switchable volume gratings in polymer-dispersed liquid crystals[J].Appl.Phys.Lett,1994,64:1074.
[7]Sutherland R L,Natarajan LV,Tondiglia V P.Bragg gratings in an acrylate polymer consisting of periodic polymerdispersed liquid-crystal planes[J].Chem.Mater,1993,5:1533.
[2]Tanaka K,Kato K,Date M.Fabrication of holographic polymer dispersed liquid crystal(HPDLC)with high reflection efficiency[J].Jpn.J.Appl.Phys,1999,38:277-278.
[3]Keiji Tanaka,Kinya Kato,Shinji Tsuru,et al.Holographically formed liquid crystal/polymer device for reflective color display[J].SID’94 Digest,1994,25:37-40.
[4]Veltri A,Caputo R,Umeton C,et al.Model for the photoinduced formation of diffraction gratings in liquid-crystalline composite materials[J].Appl.Phys.Lett,2004,84:3492-3494.
[5]李文萃,郑致刚,刘永刚,等.表面混合排列取向对全息聚合物分散液晶光栅电光特性的影响[J].光学精密工程,2010,18:1504.
[6]Natarajan L V,Sutherland R L,Tondiglia V P,et al.Electrically switchable volume gratings in polymer-dispersed liquid crystals[J].Appl.Phys.Lett,1994,64:1074.
[7]Sutherland R L,Natarajan LV,Tondiglia V P.Bragg gratings in an acrylate polymer consisting of periodic polymerdispersed liquid-crystal planes[J].Chem.Mater,1993,5:1533.