What Is a Fiber Optic Connector?
FC connector is a type of fiber optic connector, which is a terminal for optical fiber, and is used to connect optical fiber cables.
Since this optical connector is a component that connects optical fiber cables, it plays a very important role in connecting optical devices, which are precision equipment.
Fiber optic connector is metal components used for fixing optical cables that need to be tightened with screws.
Fiber optic connector, including FC connector, is one of the most important components in the construction of optical measuring instruments and optical communication systems, and various types of fiber optic connector is available on the market for use in different environments and for different applications.
Among the methods for splicing optical fibers, unlike fusion splicing, splicing using optical connectors is more versatile because the splicing part can be easily connected and disconnected manually while maintaining sufficient strength of the splicing part.
Uses of Fiber Optic Connectors
Connecting fiber optic cables using fiber optic connectors, including FC connectors, can be easily connected and disconnected by hand, while maintaining a sufficiently high level of strength in the connection area.
Therefore, the connection of optical fiber cables using optical connectors is very versatile.
Among them, fiber optic connectors are used to connect the screw-tightening method, which is used for connections where strength is required to secure optical fiber cables.
In addition to their use in optical equipment and measuring instruments, they are also used in CATV, LAN and public communication lines.
Principle of Fiber Optic Connectors
Fiber optic connectors can be classified into multi-fiber and single-fiber types, of which fiber optic connectors can be included in the single-fiber type.
Among single fiber optic connectors, FC connectors can be included in the sleeve joint method.
In the sleeve joint method, the optical fiber to be connected is first positioned and fixed in the center of a cylindrical ferrule, and then the cylindrical ferrules are aligned with each other inside the sleeve at the time of connection.
The cross-section of the sleeve is C-shaped among split sleeves, and it is spring-loaded, so the cylinders of the ferrules are held together in an optimum manner by the spring, making it easy to align the axes and angles.
In order to position the optical fiber around the cylindrical ferrule, the optical fiber is bonded through a hole that is slightly larger than the diameter of a typical optical fiber (0.125 mm) by about 0.5 μm.
Most of these cylindrical ferrules are made of zirconia among ceramics, which has a linear expansion coefficient almost equal to that of optical fibers, so that temperature changes in the storage and use environment of optical connectors are almost the same. This allows the optical fiber to be used stably without being subjected to thermal stress.
Another advantage is that the end face of the cylindrical ferrule can be polished clean together with the optical fiber.
Precautions for Using Fiber Optic Connectors
There are three points to note when using fiber optic connectors as follows.
- Operating temperature range
The upper limit of the operating temperature range requires that the ambient operating temperature plus the temperature rise of the fiber optic connectors itself must fall within the upper limit. - Storage temperature range
The storage temperature range is the storage temperature when the fiber optic connector is packaged before it is mounted. After mounting, the operating temperature range applies. - Inserting and extracting connectors
Connectors must be inserted and extracted properly all the way to the back. When inserting, it is necessary to confirm that the connector is securely locked, and when removing, it is necessary to confirm that the lock is unlocked before proceeding.
There are various other detailed precautions, so be sure to properly check the specifications of each product before use.
Factors Causing Failure of Fiber Optic Connectors
There are three major causes of fiber optic connectors failure.
- Initial failure
A pattern in which the device itself has malfunctioned before use.
・Poor contact caused by flux or cleaning fluid.
・Poor contact caused by base coating liquid - Accidental failure
Pattern of failure mainly due to mechanical or physical stress.
・Failure due to physical damage to the product
・Damage due to insertion or removal of entire cable
・Damage due to improperly oriented insertion - Abrasion failure
Failures that occur while the equipment is in use.
・Failure due to corrosion of contacts or poor contact caused by insertion/extraction exceeding the specified number of times.
・Contact failure due to use under the conditions specified in the regulations
・Damage due to wear and tear of the locking part caused by operating the locking part for more than the specified number of insertions and removals.
Lifetime of Fiber Optic Connectors
The life of fiber optic connectors can be due to poor contact or damage to the device itself, but there is no degradation over time.
The life of FC connectors can be caused by mechanical, environmental, or electrical degradation, and the life of FC connectors is greatly affected by external factors such as the environment in which the fiber optic connectors are used and the level of demand for FC connectors from the equipment to which it is connected. Among these factors, the life of a single fiber optic connectors are determined by its contact resistance and the number of times it is inserted and removed.