与偏振相关和无关的4×4自由空间光开关

设计了一种由相位型空间光调制器（PSLM）、偏振光分束器（PBS）、反射镜、半波片（HWP）和四分之一波片（QWP）构成的2×2光开关。该光开关所用器件少,具有结构紧凑规整、功能的实现与信号光的偏振态无关以及可以完成双向交换等特点。在此基础上通过2×2光开关的级联,设计了一种与偏振无关的4×4光开关的实验模块,根据其路由控制表对该实验模块功能的实现进行了分析。为与之作比较,还提出了一种与偏振相关的4×4光开关,该光开关利用对信号光偏振态的控制进行路由选择,以实现所需的交换和排序。

Polarization-Dependent and Polarization-Independent 4 × 4 Free-Space Optical Switch

A novel 2×2 optical switch, which consists of phase spatial light modulator (PSLM), polarizing beam-splitter (PBS), mirror, half-wave plate(HWP) and quarter-wave plate (QWP), is proposed. This new kind of configuration of the optical switch has the features of less optical components, compact structure, efficient performance, and insensitiveness to polarization of signal beam. In addition, the straight and the exchange functions of 2×2 optical switch are implemented bi-directionally in free-space. A optical experimental module of polarization-independent 4×4 optical switch is achieved by cascading polarization-independent bidirectional 2×2 optical switch and is analyzed according to path control table. Simultaneously, a kind of polarization-dependent 4×4 optical switch is also investigated for comparison, the exchange sort of the polarization-dependent 4×4 optical switch is achieved by control of polarization state of signal beam for routing.