液晶光学相阵列相移单元的电压-相移特性

液晶光学相阵列是一种新型的光学相位调制器件，为分析器件中相移单元的电压-相移特性，建立了液晶相移单元的数学模型，并提出了一种混合差分迭代算法。该算法根据液晶分子在电场作用下的物理变化过程，在指向矢与电位的耦合迭代过程中，采用追赶法计算相移单元中的电位分布。根据该算法对相移单元中液晶指向矢的分布进行了仿真计算，进而对取向膜厚度、预倾角和液晶盒厚度对器件的电压-相移特性的影响进行了分析。结果表明，当电压处于阈值电压与饱和电压之间时，取向膜厚度对液晶的电压-相移特性的影响比较明显。

Voltage-phase shift characteristic of phase shift unit for liquid crystal optical phased array

Liquid crystal optical phased array(LCOPA) is a novel optical phase modulator. To analyse the voltage-phase shift characteristic of the phase shift unit for LCOPA, a mathematical model of liquid crystal phase shift unit is set up, and a hybrid iterative finite-difference algorithm is proposed as well to calculate the director profile of the liquid crystal in a phase shift unit. According to the physical response process of liquid crystal molecules under electric field, the electric potential distribution in liquid crystal cell is calculated by means of Double-Sweep Method in the coupled iterative procedure of director and electric potential in this algorithm. Based on the algorithm, the influence of alignment layer thickness, pre-tilted angles and cell thickness on the voltage-phase shift characteristic of the device is discussed. Simulation results show that the influence of alignment layer thickness on the voltage-phase shift characteristic is evident on condition that the voltage is between threshold voltage and saturation voltage.