The fibers were arranged in two close-packed layers and etched thinner for crossing layer by layer, and then an FCT structure with four layers was fabricated.

• 这些光纤先被排列成双层的最密堆积，再以蚀刻的方式令其变细，接著把两片蚀刻过的双层光纤单元，以层层交叉的方式堆叠，即可组成一个拥有四层结构的面心长方光子晶体。