What are the common fiber optic connectors?

Optical fiber connectors can be divided into common silicon-based optical fiber single-mode and multi-mode connectors according to different transmission media, and other optical fiber connectors such as plastic as the transmission medium; according to the structure of the connector, it can be divided into: FC , SC, ST, LC, DIN, MU, MT and other forms.

The optical fiber connector

(1)FC type fiber optic connector

The earliest, FC-type connectors used the mating ends of ceramic pins. Such connectors are simple in structure, easy to operate, and easy to manufacture, but the fiber ends are more sensitive to dust, and are prone to Fresnel reflections, making it difficult to improve return loss performance.

Later, this type of connector was improved, and the contact pin (PC) with spherical end face was adopted, and the external structure was not changed, so that the performance of insertion loss and return loss was greatly improved.

(2) SC type fiber optic connector

The outer shell of this optical fiber connector is rectangular, and the structure and dimensions of the pins and coupling sleeves used are exactly the same as those of the FC type. Among them, the end face of the pin is mostly PC or APC type grinding method; the fastening method is a plug-in latch type, without rotation. This type of connector is inexpensive, easy to plug and unplug, small fluctuation in insertion loss, high compressive strength, and high installation density.

(3)ST type fiber optic connector

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

(4) LC type connector

The size of the pins and sleeves used by this connector is half the size of ordinary SC, FC, etc., which is 1.25mm. This can increase the density of fiber optic connectors in the fiber optic distribution frame. At present, in terms of single-mode SFF, LC-type connectors have actually occupied a dominant position, and the application in multi-mode is also growing rapidly.

(5) DIN47256 fiber optic connector

This is a connector developed in Germany. The pins and coupling sleeves used in this connector have the same structural dimensions as the FC type, and the end face treatment adopts PC grinding. Compared with the FC type connector, its structure is more complicated, and there is a spring that controls the pressure in the internal metal structure, which can avoid damage to the end face due to excessive insertion pressure. In addition, the mechanical precision of this connector is high, so the insertion loss value is small.

(6) MT-RJ type 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 on the end face of the connector is designed in a double-core (0.75mm interval) arrangement, which is mainly used for data transmission. A generation of high-density fiber optic connectors.

(7)MU type connector

The MU connector is the world's smallest single-core optical fiber connector developed by NTT based on the SC-type connector that is currently most used. The connector uses a 1.25mm diameter sleeve and a self-retaining mechanism, which has the advantage of enabling high-density mounting. Utilizing MU's 1.25mm diameter sleeve, NTT has developed the MU connector series.