Jull Ethan I L, Wahle Markus, Wyatt Peter J M, Ellis Colin, Cowling Stephen J, Goodby John W, Usami Kiyoaki, Gleeson Helen F
Opt Express. 2019 Sep 16;27(19):26799-26806. doi: 10.1364/OE.27.026799.
A dichroic dye-doped liquid crystal Fresnel lens was fabricated and investigated to observe the combination of phase and amplitude modulation based focusing. An anthraquinone dichroic dye was doped into a liquid crystal host, which when in the Fresnel lens configuration, generates a Fresnel zone plate with alternating "transparent" and "opaque" zones. The zones were induced by using photo-alignment of a light-sensitive alignment layer to generate the alternating pattern. The voltage dependency of efficiency for the dye-doped and pure liquid crystal Fresnel devices were investigated. Incorporation of dyes into the device yielded a significant 4% improvement in relative efficiency in the lens, giving a maximum of 37% achieved in the device, much closer to the theoretical 41% limit when compared with the non-dye-doped device. The input polarization dependence of efficiency was also investigated, showing very small fluctuations (±1.5%), allowing further insight into the effect of fabrication method on these liquid crystal Fresnel devices.
制备并研究了一种掺杂二向色性染料的液晶菲涅耳透镜，以观察基于相位和幅度调制的聚焦组合。将一种蒽醌二向色性染料掺杂到液晶主体中，当处于菲涅耳透镜配置时，会产生具有交替“透明”和“不透明”区域的菲涅耳波带片。通过使用光敏取向层的光取向来产生交替图案，从而形成这些区域。研究了掺杂染料和纯液晶菲涅耳器件效率的电压依赖性。在器件中掺入染料使透镜的相对效率显著提高了4%，器件中最高达到37%，与未掺杂染料的器件相比，更接近理论极限41%。还研究了效率的输入偏振依赖性，显示出非常小的波动（±1.5%），这有助于进一步了解制造方法对这些液晶菲涅耳器件的影响。
