Common fiber connector classification

Update:23 Mar 2018

FC type fiber connector This connector was first develo […]

FC type fiber connector

This connector was first developed by Japan NTT. FC is the abbreviation of Ferrule Connector, indicating that the external reinforcement method is using metal sleeves, and the fastening method is a turnbuckle. The earliest, FC-type connector, the use of the ceramic pin butt end face plane contact (FC). Such a connector has a simple structure, is easy to operate, and is easy to manufacture. However, the end of the optical fiber is relatively sensitive to fine dust, and Fresnel reflection is likely to occur. Therefore, it is difficult to improve the return loss performance. Later, this type of connector was modified to use a pin (PC) with a spherical butt-end surface, and the external structure did not change, resulting in a significant increase in insertion loss and return loss performance.

SC fiber optic connector

This is a fiber optic connector developed by NTT Japan. The housing is rectangular and the pin and coupling sleeves used have exactly the same dimensions as the FC model. The end face of the pin is mostly PC or APC-type grinding; the fastening method is the use of plug-and-pin latch type, no need to rotate. These connectors are inexpensive, easy to insert and withdraw, have small fluctuations in insertion loss, high compressive strength, and high installation density.

The ST and SC interfaces are two types of fiber optic connectors. For 10Base-F connections, the connectors are usually ST type. For 100Base-FX, the connectors are mostly SC type. The core of the ST connector is exposed, and the SC connector core is inside the connector.

Biconic Connector

The most representative of these types of fiber optic connectors is developed by Bell Labs, USA. It consists of two precision-molded heads, a truncated-cone cylindrical plug, and an internal double-tapered plastic sleeve. The coupling components of the cartridge are composed. DIN47256 fiber optic connector This is a connector developed by Germany. The pins and coupling sleeves used in this type of connector have the same dimensions as the FC type, and the end face is treated with PC grinding. Compared with the FC type connector, the structure thereof is more complicated, and the inner metal structure has a spring for controlling the pressure, so as to avoid damage to the end surface due to excessive plug pressure. In addition, the mechanical precision of this connector is high, so the insertion loss value is small.

MT-RJ connector

MT-RJ started from NTT developed MT connector with the same latching mechanism as RJ-45 type LAN electrical connector, aligning the optical fiber with guide pins installed on both sides of the small sleeve for easy communication with the optical transceiver Connected by the machine, the connector end face fiber is arranged in a twin-core (interval 0.75mm) arrangement and is a next-generation high-density fiber connector that is mainly used for data transmission.

LC type connector

The LC connector was developed by the well-known Bell Institute and is made using an easy-to-use modular jack (RJ) latch mechanism. The size of pins and sleeves used is half of the size used for ordinary SC, FC, etc., which is 1.25mm. This can increase the density of fiber connectors in the fiber distribution frame. At present, in the aspect of single-mode SFF, the connector of LC type has actually occupied the dominant position, and the application in the aspect of multimode has also grown rapidly.

MU type connector

The Miniature Unit Coupling (MU) connector is the world's smallest single-fiber connector developed by NTT based on the most widely used SC type connector. The connector uses a 1.25mm diameter sleeve and self-retaining mechanism, which has the advantage of enabling high-density mounting. With MU's 1.25mm diameter bushings, NTT has developed MU connector series. They have a socket type connector (MU-A series) for optical cable connection; a backplane connector (MU-B series) with a self-retaining mechanism and a simplified socket for connecting an LD/PD module and a plug (MU-SR series) Wait. With the rapid development of larger bandwidth and larger capacity of optical fiber networks and the wide application of DWDM technology, the demand for MU-type connectors will also increase rapidly.

MC connector

In 2012, the domestic communications company independently developed a smaller and denser MC connector than the LC connector. Rihai MC optical fiber connector is a kind of high-density single-core optical fiber connector, suitable for a variety of high-density applications, such as large-capacity center room and high-density data center. The high density of MC fiber optic connectors allows up to twice the size of an LC connector in the same space, making it the world's smallest and highest density connector today.