MACH-ZEHNDER INTERFERENCE OPTICAL PATH STRUCTURE HAVING FULL POLARIZATION MAINTENANCE FUNCTION

摘要

A Mach-Zehnder interference optical path structure having a full polarization maintenance function comprises a polarization beam splitting device (3), a first polarization maintenance relay device (4), a first Faraday rotation mirror (5), a second polarization maintenance relay device (6), a second Faraday rotation mirror (7), and a first polarization maintenance coupler (8). The first polarization maintenance relay device (4) comprises a first port, a second port, and a third port, wherein the first port receives a first polarized light output by the polarization beam splitting device (3), the second port is connected to the first Faraday rotation mirror (5), and the third port is connected to a first port of the first polarization maintenance coupler (8). The second polarization maintenance relay device (6) comprises a first port, a second port, and a third port, wherein the first port receives a second polarized light output by the polarization beam splitting device (3), the second port is connected to the second Faraday rotation mirror (7), and the third port is connected to a second port of the first polarization maintenance coupler (8). The structure is applicable to long-distance distributed optical fiber sensing, such as monitoring of optical fiber communication trunks, security monitoring of long-distance perimeter and oil and natural gas pipelines, etc.