The connection of the optical fiber is divided into two […]
The connection of the optical fiber is divided into two types: a fiber active connection and a fiber fixed connection.
(1) Fiber optic connection
The active connection of the fiber is achieved through a fiber optic patch cord.
(2) Fiber optic fixed connection
Optical fiber fixed connection is the most common type used in optical cable engineering. It is characterized in that the optical fiber can not be disassembled after being connected once, and is mainly used for permanent connection between optical fibers in the optical cable line. Requirements: The connection loss should be small (O.1 dB or less); the stability of the connection loss should be good. There should be no additional loss when the temperature changes within a range of 20 °C to +60 °C; it has sufficient mechanical strength and service life; The connector is small in size; easy to handle; easy to place and protect. At present, the optical fiber fixed connection has a fusion method and a non-welding method.
1 non-welding method. Also known as the bonding method, it uses a simple clamp to trap the fiber and fix it with a binder to achieve a low-loss connection of the fiber. Non-welding methods mainly include: V-groove method, casing method and 3-core fixing method. The non-welding method is characterized by a simple operation method and does not require an expensive fusion splicer, but the connection loss is large, generally about 0.2 dB. The non-welding method is suitable for occasions with special requirements, such as oil fields, warehouses, etc.
2 welding method. The characteristics of the welding method: low welding loss, safe and reliable, less affected by the outside world, but need a more expensive welding machine. It is the main connection method for the construction and maintenance of optical cable lines.
The operation steps of the welding method are as follows.
· Processing of fiber end faces. First remove the loose tube of the fiber, wipe off the filling grease on the fiber, and determine the placement position and direction of the fiber contact of each unit on the fiber disc (marked if necessary), and cut off the required length of the remaining fiber. Excess fiber. Pass the heat-shrink tubing on one side and peel off the coating one or two times. Secondly, the bare fiber is cleaned, and the bare fiber is repeatedly wiped with cotton yarn and alcohol until it emits a "beep" friction sound. Finally cut the fiber section to ensure that the fiber axis is perpendicular to the cutting blade.
· Fiber optic connection installation. The optical fibers with the processed end faces are respectively clamped on the left and right fiber clips, and the end faces are 0.5 to 1.5 nm away from the discharge needle.
· Protection of the fiber connector. Carefully observe the display status on the screen, ask the monitor, take out the connected fiber, move the heat shrink tube to the fusion joint, place the bare fiber in the middle of the tube, put them together into the heater, and start the heater.
· The retention of surplus fiber. Heat shrinking and cooling the heat shrinkable tube of each fiber unit (group) one by one. Place the surplus fiber in the remaining slot in the pre-arranged slot. During this process, small circles and optical fibers with a diameter of less than 2 cm should be prevented from being squeezed and bent.