1. Introduction of optical switch
An optical switch is an optical device with 1 or N channels to choose from, which can switch the optical signal from one channel to another, thereby realizing optical path conversion. According to different principles, there are many types of optical switches. At present, mechanical optical switches are widely used, which mainly rely on moving optical fibers or optical components to switch the optical path.
The mechanical optical switch uses a mechanical device to move the optical fiber or other components to guide the light from the input port to the output port. There are three main principles of application according to the different driven components:
1. Mobile fiber type:
2. Mobile prism type:
3. Mobile mirror type:
Although the mechanical optical switch is widely used and has low cost, its large size and difficulty in large-scale integration limit its future application in optical communication. With the continuous advancement of technology, MEMS (Micro-Electro-Mechanical) optical switches have become the development direction of optical switches for large-capacity optical network switching. It is a new type of mechanical optical switch that combines MEMS and traditional optical technology, and has the characteristics of low loss, low crosstalk and high extinction ratio of mechanical optical switches. At the same time, it also has the characteristics of small size, low polarization loss and fast switching speed.
The principle of MEMS optical switch application is mainly based on micro transmission mirror and micro mirror.
The transmission mirror and mirror in the optical switch can be rotated in multiple directions
Second, the application of optical switches
Optical switch interface types are 1×1, 1×2, 2×2 and M×N. The following will explain their applications:
1×1 Optical Switch
The connection and disconnection of the optical path can be realized by opening and closing.
1×2 Optical Switch
The main route can fail, and the optical route can be switched to the backup route.
2×2 Optical Switch
This type of optical switch is widely used. It is used in OADM node equipment for wavelength division multiplexing of backbone network and metropolitan area network. It can realize dynamic configuration of services and enhance the flexibility of nodes in the entire network system. At the same time, the problematic services under the node can be switched to the backup route. Thereby improving the stability of the entire network.
M×N Optical Switch
Often used for network monitoring, optical device testing, and switching cores for building optical cross-connect equipment.
