How do fiber optic connectors achieve precise alignment between fibers?

When the two optical fibers are connected, due to the difference in position, shape and structure of the two optical fibers, the energy cannot be 100% transferred from one fiber to the other, that is, the connection loss will occur. The two connected fibers must be precisely aligned to ensure low loss.The main function of the optical fiber connector is to connect two optical fibers quickly, so that the optical signal can be continuous to form an optical path. How do fiber optic connectors achieve precise alignment between optical fibers?

The types of fiber optical connectors are variable. However, the basic warranty for precise alignment between optical fibers depends on two factors. The first is ceramic ferrules with precise inner diameter, outer diameter and concentricity, which is warranted by mechanical fabrication of ceramics. The second is ceramic sleeves with a cleft, which is a clever design. Fig.1 shows how two optical fibers are aligned through a ceramic sleeve. The inner diameter of sleeve is a little smaller than the outer diameter of the ferrules. The ferrules can be inserted into the sleeve because of the cleft. The expanded sleeve constricts the ferrules to ensure precise alignment.

Fig.1 Alignment between two optical fibers

The core size of the single mode fiber (SMF) is about 8~10?m. The two connected fibers must be precisely aligned to ensure low loss. Fig.2 shows how much the lateral offset between two optical fibers influence the IL. The curve is exponential. A small lateral offset such as 2.4?m will introduce IL of 1dB. Thus the lateral offset between the two fibers must be kept 65dB.

Fig.4 Relationship between the added return loss and angle of the endface

Fiber optic connectors are the most basic optical passive components for optical fiber communication systems. The basic specification requirements for them are low insertion loss (IL) and high return loss (RL), i.e. low back reflection (BR). However, as the most widely employed components, low cost and easy connection are equal important as the specifications.

About HYCHYC Co., Ltd was founded in 2000. It is a leading passive optical device OEM / ODM and solution provider in the global industry, focusing on R&D, manufacturing, sales and service of passive devices for optical communication. The company's main products are: optical fiber connectivity products, WDM wavelength division multiplexers, PLC optical splitters, and MEMS optical switches, which is widely used in 4G / 5G networks, Telecom, Data centers, etc.http://www.hyc-system.com

Marketing at HYC Co., Ltd, a China manufacturer of fiber connectivity,WDM, PLC splitter and high-density datacom cabling over 19 years.