研制了一种基于窄带薄膜滤光片的可重构的光分插复用器(ROADM),它由三个单芯光纤准直器、一对三端口光环形器、一对全反射镜和一片特别设计的角度调谐窄带多腔薄膜滤光片组成。通过步进电机的推动调制角度调谐滤光片的倾斜入射角度,从而实现了可选择波长上下路。对该可重构的光分插复用器进行了实验研究,并对该器件的串扰特性进行了详细的分析与计算。实验中得到的上下路信道隔离度大于34 dB,可调谐范围大于26 nm,与理论计算结构相符。该种新型的ROADM具有结构简单、可调谐范围大、隔离度高、低偏振相关损耗、成本低等特点,可广泛应用于各种密集波分复用(DWDM)光网络。

A novel reconfigurable optical add-drop multiplexer (ROADM) based on narrowband thin-film filter is proposed. The ROADM consists of three single-fiber collimators, a pair of three-port optical circulators, a pair of mirrors and one particularly designed angle-tuned narrowband multiple cavities filter. By control a stepping motor to change the incident angle of the thin-film filter, the ROADM can add or drop a selective wavelength. The characteristics of the ROADM are studied experimentally, and especially the crosstalk is analyzed and calculated in detail. In the experiment, the channel isolation is more than 34 dB and its tunable range is over 26 nm, which coincide with the results of theoretical calculation. The RAODM has many advantages such as simple structure, wide tunable range, high isolation, low polarization-dependent loss, low cost and so on. It can be widely used in practical DWDM system.