Types of fiber optic connectors

- Jan 18, 2018-

Types of fiber optic connectors

According to different classification methods, fiber optic connectors can be divided into different types, according to the different transmission media can be divided into single-mode fiber connectors and multimode fiber connectors; according to the structure can be divided into FC, SC, ST, D4 , DIN, Biconic, MU, LC, MT and other types; according to the connector pin end can be divided into PC (UPC) and APC;

In the practical application process, we generally make the distinction according to the structure of the optical fiber connector. The following is a brief introduction of some of the more common fiber connectors:

(1) FC optical connector

This connector was first developed by Japan NTT. FC is the acronym for Ferrule Connector, indicating that its external reinforcement is the use of metal sleeve, fastening the way for the buckle. The earliest, FC type connector, the use of ceramic pins mating face is the plane contact method (FC). Such connectors are simple in structure, easy to operate and easy to manufacture. However, the fiber end face is more sensitive to dust, and it is easy to produce Fresnel reflection and it is difficult to improve the return loss performance. Later, this type of connector has been improved, the use of docking the spherical end of the pin (PC), while the external structure has not changed, making the insertion loss and return loss performance has been greatly improved.

(2) SC type optical fiber connector

This is a kind of optical fiber connector developed by Japan NTT Corporation. The shell is rectangular, the use of pin and coupling sleeve structure and size exactly the same FC type, pin end face more PC or APC grinding method; fastening method is the use of plug pin type, not Rotate. Such connectors are inexpensive, easy to plug and unplug, low insertion loss variations, high compressive strength, and high installation density (most on router switches).

(3) ST type optical fiber connector

ST type optical fiber jumper: commonly used in optical fiber distribution frame, the shell is round, fastening means for the screw buckle. (For 10Base-F connection, the connector is usually ST type. Commonly used in fiber patch panels)

(4) LC type optical fiber connector

The LC connector was developed and researched by the renowned Bell Institute and is made using an easy-to-use modular jack (RJ) latch mechanism. The pins and sleeves used are half the size of normal SC, FC, etc. and are 1.25mm. This increases the density of fiber optic connectors in optical distribution frames. Currently, in the single-mode SFF, LC type of connector has actually occupied the dominant position, the application of multi-mode is also growing rapidly.

(5) Biconic Connector

Developed by Bell Laboratories in the United States, the most representative of these fiber optic connectors consists of two precision-molded ends with a frusto-conical cylindrical plug and a double-ended plastic sleeve Tube coupling components.

(6) DIN4 type optical fiber connector

This is a connector developed by Germany. The pins and coupling sleeves used in this connector are the same size as the FC type and the PC process is used for the end face processing. Compared with the FC type connector, the structure is more complex, and the internal metal structure has a control pressure spring to prevent the end face from being damaged due to the excessive insertion pressure. In addition, this connector has higher mechanical accuracy and therefore smaller insertion loss values.

(7) MT-RJ type connector

MT-RJ started with the MT connector developed by NTT with the same latching mechanism as the RJ-45 type LAN electrical connector. Alignment of the optical fiber with guide pins mounted on both sides of the small bushing made it easy to communicate with the optical transceiver Machine connected, the connector end of the optical fiber for the double core (0.75mm spacing) array design, is mainly used for data transmission next generation high-density optical connector.

(8) MU type connector

The MU connector is the world's smallest single-core fiber optic connector developed by NTT based on the currently most used SC-type connector. The connector uses a 1.25mm diameter sleeve and self-holding mechanism, which has the advantage of Can achieve high-density installation. NTT has developed a family of MU connectors using MU's 1.25mm diameter bushings. They have socket type optical connectors (MU-A series) for optical cable connections, backplane connectors with self-holding mechanism (MU-B series), and simplified sockets for connecting LD / PD modules and plugs )Wait. Demand for MU-type connectors will also grow rapidly as fiber-optic networks become more capable of larger bandwidths and DWDM technologies are widely used.