水下湿插拔接触式光纤耦合设计与性能分析

Design and performance analysis of contact fiber-coupled of underwater wet-mateable connector

水下连接器是水下观测网的关键零部件,采用油液密封方式实现低损耗连接,但该方式会导致光连接结构复杂、工程研制难度大。为解决此问题,对比陆基光纤网络的连接方式,提出接触式光纤连接器水下原位湿插拔的方案。基于水体吸收特性、朗伯-比尔定律以及液体的表面张力等理论进行原理分析,在光纤端面形成厚度在5μm以内的水膜且该厚度水膜对1310,1550 nm波段的吸收损耗可忽略不计;然后,以1550 nm波段为例,对光纤在空气、水、硅油的耦合损耗情况进行实验分析,并利用设计的光插针结构进行性能验证。实验数据显示,光纤水下原位湿插拔的平均损耗为0.17dB,光插针的原位湿插拔平均损耗为0.23 dB。由此表明,接触式光纤耦合设计能够满足水下湿插拔的低损耗连接要求。本文为水下光纤湿插拔连接器领域提供了新思路,提出在确保水体清洁的情况下可直接进行水下原位湿插拔的设计方案,有望打破国外以油液密封方式建立的技术垄断。

Underwater connector is an important part of the seafloor observation.Currently,the oil-filled sealing structure is complicated and it’s hard to design in project.To solve this problem,contrast the connection mode of the land-based fiber network,we presented a novel design for the contact fiber-coupled based on underwater wet-mateable the fiber connector.First,based on the analysis of Beer-Lambert law,water absorption properties and surface tension of liquid theory,we identified the ability to form the water film thickness within 5μm at the optical fiber end faces.This thin layer water exhibit negligible absorption of the 1310/1550 nm because of the absorption loss can be kept within the predefined target range.The study was conducted that the loss analyses is summarized by using optic fiber in air,water,and oil based on 1550 nm.Finally,we designed the novel optical structure based on this idea and analyzed their transmission performance.The results showed that the summary of the transmission loss is 0.17 dB and the loss measurement in the new fiber connector is 0.23 dB.The findings show that the design of the contact fiber-coupled of underwater wet-mateable is meeting the low loss requirements.Therefor,we can directly implement in-situ wet-mate interconnects in the water rather than the silicone oil based on the surface cleaning.This paper provides a new design for the optical lines in underwater wet-mate connector.This idea is expected to break the Intellectual property that built upon the work of the sealing technique of the oil-filled.