Liquid crystal fluctuations and device performance

电信领域的性能规格非常严格，主要是因为网络元素可能 层叠，这样不完美的地方可能会病理性地结合在一起。“噪音”的一个来源是光量 在不应该存在的特定波长上散射到输出光纤中--甚至50db 低于信号电平是有问题的。 许多光学设备使用液晶来实现开关。液晶是光学各向异性的 液体，从而能够以适中的切换场切换光轴。然而，作为液体，它们 也容易受到各向异性轴的波动的影响。这些波动被称为指向矢波动。 指向矢波动以光噪声的形式出现在信号中。液晶也具有一些特性 晶体的特征：各向异性弹性。此外，液晶通常是薄的。 因此，表面效应也很重要：所有这些都会产生弹性扭曲。二 变形模式，一个与分子在表面的倾斜有关，另一个与扭曲模式有关，特别是 在薄液晶盒中很重要。 该建议的目标是检查特定的基于液晶的光学系统中的光学噪声源 称为LCOS单元的设备。光学噪声对不同液晶参数的依赖关系 将对LCoS单元进行研究，以期找到减少或解决如何减少光学 噪音。这将提高公司制造的下一代设备的质量，并确保 这些未来设备的收入将最大化。

Performance specifications are very tight in telecommunications, mostly because network elements may cascade so that imperfections might combine pathologically. One source of 'noise' is the amount of light scattered into an outgoing fibre at a particular wavelength that is not supposed to be there - even levels 50dB below the signal level are problematic. Many optical devices employ liquid crystals to enable switching. Liquid crystals are optically anisotropic liquids, and thus enable switching of the optic axis with moderate switching fields. However, being liquid, they are also susceptible to fluctuations in the anisotropy axis. These fluctuations are called director fluctuations. Director fluctuations present themselves as optical noise to the signal. Liquid crystals also have properties characteristic of crystals: anisotropic elasticity. In addition, liquid crystals are usually made as thin sandwich-like films, therefore surface effects are important as well: all produce elastic distortions. Two distortion modes, one pertaining to molecular tilt at the surface and the other to the twist mode, are particularly important in thin liquid crystal cells. The goal of this proposal is to examine the source of optical noise in a particular liquid-crystal based optical device known as the LCOS cell. The dependencies of the optical noise on various liquid crystal parameters in LCOS cells will be studied, with a view to finding a solution that reduces or addresses how to reduce optical noise. This will enhance the quality of next-generation devices that the company makes, and ensure that revenues for these future devices are maximized.