在光学多级互连网络的实现中，光学2×2开关的构造是至关重要的。本文介绍一种构成光寻址2×2光学开关的方法，该方法是在方解石晶体的双折射性质的基础上，利用普克尔斯只读光调制器(PROM)来控制入射光的偏振态，从而实现光寻址2×2光学开关，这种开关具有许多优点，并且可以在3-D方向堆栈集成。利用该开关可以很方便地实现3-D集成的蝶形互连网络。

The optical 2×2 switching is the key part of the implementation of the optical multistage interconnection network. In this paper, a method to construct the optical addressed 2×2 switching is presented. It is based on the birefrigence property of the calcite crystal, and the PROM device is used to control the polarization of the input light. This photonic switching has many advantages, and it can be stacked in 3 D directions. The 3 D stacked butterfly network is easy to implement by using this switching.