4×4自由空间光开关结构及其矩阵分析

4×4 Free-Space Optical Switch Structure and Its Matrix Analysis

光开关是全光通信网络中的一种重要的光无源器件。提出了一种4×4自由空间光开关的结构设计方法,并进行了矩阵理论分析。该4×4光开关具有新颖的光模块化结构,该光开关结构仅由偏振分束组合棱镜,λ／4波片,λ／2波片,直角棱镜,全反镜和偏振光调制器组成,对光开关的控制与输入光束的偏振态无关。所有的输出端口可以和输入端口无阻塞地互连交换。这种新型的光开关结构具有光学元件少,结构紧凑,模块化,与偏振无关的特点。基于4×4光开关的矩阵分析得到了路由控制表,为4×4光开关从任意输人端口到任意输出端口的路由控制状态提供了理论分析手段,从而可以方便地实现无阻塞地光交换开关矩阵的路由控制功能。

Optical switch is a kind of important passive optical components in all-optical communication network. A kind of optical structure design method of 4 × 4 free-space optical switch is presented and a matrix theoretical analysis is made for this 4×4 optical switch structure. The 4×4 optical switch has a novel optical module configuration. It consists of polarization beam splitter, 1/4 wave plate, 1/2 wave plate, polarization optical modulator, right angle prism, and total reflection mirror. The operation is independent of the polarization states of input optical signals. Non-blocking optical switching can be implemented between input channels and output channels. This new kind of optical switch structure has the features of less optical components, compact size, modularity, polarization-independent. The routing control table for the 4×4 optical switch is given based on the matrix analysis. It provides a theoretical analysis method to describe routing controlling states between any one of the input channel and any one of the output channel of the 4×4 optical switch. So the routing controlling function of the non-blocked optical switching matrix can be realized expediently.