Speckle contrast reduction of laser light using a chiral nematic liquid crystal diffuser
Speckle contrast reduction of laser light using a chiral nematic liquid crystal diffuser
复制标题
DOI：
10.1063/1.4971997
复制
发表时间：
2016-12-26
影响因子：
4
通讯作者：
Morris, Stephen M.
中科院分区：
文献类型：
--
作者：
Hansford, David J.;Fells, Julian A. J.;Morris, Stephen M.
激光的高相干性引起空间分布的干扰，称为散斑。在全息投影等应用中，这种不良的副作用会降低图像的清晰度。目前减少斑点的方法，如旋转磨砂玻璃扩散器，需要额外的笨重的移动部件。在这里，我们提出了一种基于紧凑的电流体动力学手性向列液晶装置的替代技术。入射光的空间随机相位调制是通过交变电场引起的电流体动力学不稳定性来实现的。使用掺杂离子化合物的手性向列液晶器件，我们发现散斑对比度可以降低多达80%。(C) 2016。
High coherence in laser light causes spatially distributed interference called speckle. In applications such as holographic projection, this undesirable side effect degrades image clarity. The current methods of speckle reduction, such as a rotating ground-glass diffuser, require additional bulky moving parts. Here, we present an alternative technology based upon a compact, electrohydrodynamic chiral nematic liquid crystal device. A spatially random phase modulation of the incident light is achieved through the electrohydrodynamic instabilities that are induced by an alternating electric field. Using a chiral nematic liquid crystal device that is doped with an ionic compound, we find that the speckle contrast can be reduced by as much as 80%. (C) 2016 Author(s).