Feng Wenbin, Liu Zhiqiang, Ye Mao
Opt Express. 2022 Aug 1;30(16):28941-28953. doi: 10.1364/OE.464526.
A positive-negative tunable liquid crystal lens array is proposed by electrode design. The electrode structure consists of two main units, one of them is used to generate parabolic voltage profile and the other one distributes the voltage homogeneously across the lens aperture. The proposal features the advantages of high-quality performance, simple fabrication process (a single lithographic step), compact design, low voltages and simple driving method. In addition, the lens array can be driven as a square lens array or a rotatable cylindrical lens array. The voltage difference between the electrodes on the inner face of two substrates is controlled within the range that the phase of liquid crystal layer responds linearly to voltage difference, then the phase of the lens array maintains parabolic profile in the whole focus range. In experiments, a lens array with 30 µm liquid crystal layer is fabricated using the designed electrode. The size of the array area is 11 × 11 mm, and the side length of an individual square lens is 1.0 mm. The results show that the phase profile matches with the parabolic profile during focus tuning, and good focusing effect of the positive lens is observed. As a result, a liquid crystal lens array with high-quality performance is experimentally demonstrated, and the experimental results are consistent with the theoretical analyses.
通过电极设计提出了一种正负可调液晶透镜阵列。电极结构由两个主要单元组成，其中一个用于产生抛物线电压分布，另一个用于在透镜孔径上均匀分布电压。该方案具有性能优良、制造工艺简单（单个光刻步骤）、设计紧凑、电压低和驱动方法简单等优点。此外，该透镜阵列可以作为方形透镜阵列或可旋转圆柱透镜阵列来驱动。将两个基板内表面上的电极之间的电压差控制在液晶层的相位对电压差呈线性响应的范围内，然后透镜阵列的相位在整个聚焦范围内保持抛物线分布。在实验中，使用设计的电极制造了具有30 µm液晶层的透镜阵列。阵列区域的尺寸为11×11 mm，单个方形透镜的边长为1.0 mm。结果表明，在聚焦调谐过程中相位分布与抛物线分布相匹配，并且观察到正透镜具有良好的聚焦效果。因此，通过实验证明了一种具有优良性能的液晶透镜阵列，实验结果与理论分析一致。
