SBIR Phase II: Thresholdless Ferroelectric Liquid Crystals

这个小型企业创新研究第二阶段项目的目标是制造一种商业质量的液晶，展示无滞后的V型开关。这种液晶将用于灰度级显示和电信光开关。铁电液晶(FLC)由于其快速的开关速度和宽视角，与更常用的向列相液晶相比具有固有的优势。然而，当在显示器中使用时，它们有一个缺点--它们通常只能驱动到两种状态：开和关。由于显示器需要中间的灰度状态，因此目前Flc通过快速开启和关闭来获得灰度。该项目使用了一种新型的FLC，除了其速度和视角优势外，还显示了SANALLOG切换。这种材料以前被称为“无阈值反铁电体”，现在被认为是一种对外加电场具有线性光学响应的FLC(也称为“V形开关”)。该项目的目标是制造新的显示出V形开关的液晶化合物和混合物。为此，人们提出了各种核、手性尾巴和尾巴，所有这些都已知或怀疑能促进De Vries类型近晶A的形成。通过组合这些不同的组分，将合成大约50-100个液晶。这些新的LC将与在第I阶段或更早阶段制造的LC结合在一起，提供理想的混合物，不仅具有De Vries近晶A相，而且具有宽室温近晶C相、良好的低压模拟电光响应、良好的对准性和快速无磁滞开关。将确定最佳对齐层配置。新配方的混合物将被放置在含有这种取向层的单元中，以提供V形开关显示。这个项目可能有助于促进我们对FLC中V形开关的根本原因的了解，并通过延伸，增加对自组装分子对外力的反应的洞察。此外，由于对准层与液晶的相互作用对于V型开关来说是至关重要的，因此该项目将更好地了解对准层与液晶的相互作用。

This Small Business Innovation Research Phase II project's goal is a commercialquality liquid crystal exhibiting V-shaped switching with no hysteresis. This LC will beused in gray-scale displays and telecommunications optical switches.Ferroelectric liquid crystals (FLCs), due to their fast switching speed and wideviewing angle, have inherent advantages over the more commonly used nematic liquidcrystals. However, when used in displays, they have a disadvantage - they generally canbe driven to only two states, on and off. Since displays require intermediate gray states,FLCs currently attain gray scale by rapidly switching on and off. This project uses a newtype of FLC which, in addition to its speed and viewing angle advantage, also showsanalog switching. This type of material, previously known as a "thresholdlessantiferroelectric", is now known to be an FLC with a linear optical response to appliedfield (also known as "V-shaped switching").This project's objective is to make new liquid crystal compounds and mixtures thatexhibit V-shaped switching. Towards that end, a variety of cores, chiral tails, and achiraltails, all of which are either known or suspected to promote a de Vries-type smectic A,have been proposed. About 50 - 100 liquid crystals will be synthesized by combiningthese various components. These new LCs will be combined with LCs made in the PhaseI or earlier, giving mixtures that ideally will have not only a de Vries smectic A phase,but also a wide room-temperature smectic C phase, good low-voltage analog electroopticresponse, good alignability, and fast hysteresis-free switching. An optimal alignmentlayer configuration will be determined. The newly formulated mixtures will be placed incells containing this alignment layer to give V-shaped switching displays.This project could be instrumental in advancing our knowledge of the root causes ofV-shaped switching in FLC and, by extension, add insight into the responses of self-assembling molecules to applied forces. In addition, since the interaction of the alignmentlayer with the liquid crystal is crucial for V-shaped switching, much more so than fortypical FLCs, this project will provide a better understanding of the alignment layer-LCinteractions.