What is the principle of optical switch?
author: liu
2023-03-13
Optical Switch (OS) is mainly used to realize physical switching or other logical operations of Optical signals in optical paths, and is often used as a key component of optical path switching in optical Cross-connect technology. Optical switch is a device that converts optical signals from one optical channel to another optical channel within a certain range. With one or more optional transmission Windows, optical switch is a core device that realizes optical cross-connection, optical diFF multiplexing, network monitoring and self-healing protection. The optical switch has one or more selectable transmission Windows, which can be divided into 2×2, 1×N, M×N port configurations. Optical switch has a wide range of applications in optical fiber communication system, its implementation technology is various, including: mechanical optical switch, thermooptic switch, acoustooptic switch, electro-optical switch, magneto-optical switch, liquid crystal optical switch and MEMS optical switch, etc. Mechanical optical switch and MEMS optical switch are two kinds of optical switches widely used at present. Mechanical optical switches work by physically moving optical fibers through a mechanical device to redirect optical signals. By moving a prism or directional coupler, the input light is directed to the desired output port. There are three main types of mechanical optical switches: one is using prism switching optical path technology, the other is using mirror switching technology, and the third is switching optical path by moving optical fiber. MEMS optical switch is based on micro-electro-mechanical system, which uses optical micromirror or optical mirror array to change the propagation direction of light beam to realize optical path switching. The principle of MEMS optical switch is very simple. When optical switching is carried out, the Angle of MEMS micromirror is moved or changed by electrostatic force or magnetic power to switch the input light to different output ends of the optical switch to realize the switching and on-off of the optical path. With the rapid development of optical communication, the position of optical interconnection and optical switching as optical network nodes is becoming more and more important, and the application of optical switch is becoming more and more extensive. The MEMS optical switch has the advantages of compact, fast switching speed and easy expansion. At the same time, the mechanical optical switch has the advantages of low insertion loss, low crosstalk, low polarization sensitivity, high extinction ratio, and the waveguide switch has the advantages of high switching speed, small size and easy large-scale integration. Will be the main direction of large capacity switched optical network switch development.
Optical switches play a very important role in optical networks. Optical switches can be used in Wavelength adaptation, regeneration and clock extraction in Wavelength Division Multiplexing (WDM) transmission systems. Optical switch can be used for demultiplexing in Optical Time Division Multiplex (OTDM) system. Optical switch is a key component of optical Cross-connect (OXC) and wavelength conversion in all optical switching systems. According to the number of input and output ports of the optical switch, it can be divided into 1×1, 1×2, 1×N, 2×2, 2×N, M×N, etc., they have different uses in different occasions. Its application scope mainly includes: optical network protection switching system, optical source control in optical fiber testing, real-time network performance monitoring system, optical device testing, OXC equipment exchange core construction, optical plug/division multiplexing, optical testing, optical sensing system, etc.
