介绍了一种通过使用多个薄膜法布里-珀罗滤光片的叠加来实现密集波分复用中使用的梳状滤波器的设计的新方法.采用间隔层为熔融石英的薄膜法布里-珀罗滤光片作为基本结构的光学梳状滤波器可以比较容易地控制各腔的厚度,因而能精确地达到波分复用系统中波长间隔非常窄的要求.分析了如何确定间隔层厚度和各法布里-珀罗腔的反射镜的反射率以及它们之间的匹配问题,最后给出了与设计吻合较好的实验结果,制作的梳状滤波器在C波段的信道间隔为100 GHz,相邻通道窜音小于-24 dB,最小插入损耗约-0.4 dB.

A novel designing method for optical interleaver based on cascaded solid thin film Fabry-Perot filter is presented. It′s easy to control the thickness of the spacer of the device when employing the fused quartz as the material of the spacer,so the thin film interleaver can satisfiedly meet the demand of the narrow wavelength gap for the DWDM system. The analysis on how to ascertain the thickness of the spacer,the numbers of thin film Fabry-Perot filters and the match of the reflective index of each Fabr-Perot filter's mirrors are given. The experimental result is coincident with the designed one well, and the device achieves to 100 GHz spaced channels, at wavelength around C band, with adjacent channel's cross-stalk less than -24 dB and the minimum insertion loss nearly 0.4 dB or so.