What are the common optical fiber connectors

According to different transmission media, optical fiber connectors can be divided into common single-mode and multi-mode connectors of silicon-based optical fiber, as well as other optical fiber connectors with plastic as transmission media; According to the structure of connector, it can be divided into FC, SC, St, LC, DIN, mu, MT and other forms.

(1) FC type optical fiber connector

Earlier, FC type connectors used the butt end of ceramic pins. This kind of connector has the advantages of simple structure, convenient operation and easy fabrication, but the optical fiber end is sensitive to micro dust, and it is easy to produce Fresnel reflection, so it is difficult to improve the return loss performance.

Later, this type of connector was improved by using the pin (PC) with spherical butt end face, and the external structure was not changed, which greatly improved the performance of insertion loss and return loss.

(2) SC type optical fiber connector

The shell of the optical fiber connector is rectangular, and the structural dimensions of the pin and coupling sleeve are exactly the same as those of FC type. The end face of the pin is mostly polished by PC or APC; The fastening method is plug-in pin latch type without rotation. This kind of connector has the advantages of low price, convenient plug-in operation, small fluctuation of intervention loss, high compressive strength and high installation density.

(3) St type optical fiber connector

St and SC interfaces are two types of optical fiber connectors. For 10base-f connection, the connector is usually st type, and for 100base FX, the connector is mostly SC type. The core of St connector is exposed, and the core of SC connector is in the connector.

(4) LC type connector

The size of the pin and sleeve used in this connector is half that of ordinary SC and FC, which is 1.25mm. This can improve the density of optical fiber connectors in the optical fiber distribution frame. At present, in terms of single-mode SFF, LC connector has actually occupied a dominant position, and its application in multimode is also growing rapidly.

(5) Din47256 optical fiber connector

This is a connector developed by Germany. The structural dimensions of the pin and coupling sleeve used in this connector are the same as those of FC type, and the end face is treated by PC grinding. Compared with FC connector, its structure is more complex. There is a spring to control the pressure in the internal metal structure, which can avoid damaging the end face due to excessive insertion pressure. In addition, the mechanical accuracy of this connector is high, so the intervention loss value is small.

(6) MT-RJ connector

MT-RJ aligns the optical fiber through the guide pins installed on both sides of the small sleeve. In order to facilitate connection with the optical transceiver, the optical fiber at the end face of the connector is a double core (0.75mm apart) arrangement design, which is the next generation of high-density optical fiber connector mainly used for data transmission.

(7) Mu type connector

Mu connector is the world's small single core optical fiber connector developed by NTT based on the currently used SC connector. The connector adopts a 1.25mm diameter sleeve and a self retaining mechanism, which has the advantage of high-density installation. NTT has developed Mu connector series using Mu's l.25mm diameter casing.