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Optical Fiber Connector Handbook 1 OPTICAL FIBER WhiCONNECTORt HANDBOOKe Paper JUL 2017 Optical Fiber Connector Handbook Bernard Lee Tom Mamiya 2 OPTICAL FIBER CONNECTOR HANDBOOK 3 OPTICAL FIBER CONNECTOR HANDBOOK Optical Fiber Connector Handbook Contents 6 Introduction to SENKO 7 Basic of Optical Fiber 7 Introduction to Optical Fiber 7 Optical Fiber Connectivity 8 Fiber Optic Connectors 8 Basics of Fiber Optic Connectors 9 Fiber Optic Connector Assembly 12 Connector Assurance (GR-326-CORE) 14 Service Life Test 16 Extended Service Life Test 17 Random Mating Loss Performance 18 Connector Testing 18 Insertion Loss 20 Return Loss 22 Introduction to Test Equipment 22 Power Meter & Light Source 22 Limitations 22 Optical Time Domain-based Measurement (OTDR) 23 Limitations 23 Backscatter Coefficient Settings 23 Index of Refraction (IOR) 23 Mode Field Diameter (MFD) Mismatch 24 Dead Zone 24 Helix Factor 4 OPTICAL FIBER CONNECTOR HANDBOOK Optical Fiber Connector Handbook Contents 25 Optical Continuous Wave Reflectometer (OCWR) 25 Limitations 26 Testing Procedure 26 Insertion Loss Measurement with Power Meter & Light Source 26 Cut-back Method 26 Substitution Method 27 Insertion Method 27 Insertion Loss Measurement with OTDR 28 Return Loss Measurement with OTDR 29 Return Loss Measurement with OCWR 30 Connector Hygiene 30 Overview 31 Optical Connector Ferrule & Contamination 32 Inspection Standards 34 Inspection Tools 35 Inspection Tools for MPO Connectors 36 Cleaning Tools 38 Cleaning Challenges for MPO Connectors 39 IEC Connector Type 39.1 IEC 61754-2 BOFC Connector 39.2 IEC 61754-3 LSA Connector 39.3 IEC 61754-4 SC Connector 39.4 IEC 61754-5 MT Connector 39.5 IEC 61754-6 MU Connector 39.6 IEC 61754-7 MPO Connector 5 OPTICAL FIBER CONNECTOR HANDBOOK Optical Fiber Connector Handbook Contents 39.7 IEC 61754-8 CF08 Connector 39.8 IEC 61754-9 DS Connector 39.9 IEC 61754-10 Mini MPO Connector 39.10 IEC 61754-12 FS Connector 39.11 IEC 61754-13 FC Connector 39.12 IEC 61754-15 LSH Connector 39.13 IEC 61754-16 PN Connector 39.14 IEC 61754-18 MT-RJ Connector 39.15 IEC 61754-19 SG Connector 39.16 IEC 61754-20 LC Connector 39.17 IEC 61754-21 SMI Connector 39.18 IEC 61754-22 F-SMA Connector 39.19 IEC 61754-23 LX.5 Connector 39.20 IEC 61754-24 SC-RJ Connector 39.21 IEC 61754-25 RAO Connector 39.22 IEC 61754-26 SF Connector 39.23 IEC 61754-27 M12 Connector 39.24 IEC 61754-28 LF3 Connector 39.25 IEC 61754-29 BLINK Connector 39.26 IEC 61754-30 CLIK! Connector 39.27 IEC 61754-31 N-FO Connector 39.28 IEC 61754-32 DiaLINK Connector 39.29 IEC 61754-34 URM Connector 61 Biography 6 OPTICAL FIBER CONNECTOR HANDBOOK Introduction to SENKO SENKO Advanced Components is a wholly owned subsidiary of the SENKO Group, which is headquartered in Yokkaichi, Japan. From its humble beginnings in 1946, the SENKO Group currently has an estimated annual revenue of $1.4 billion globally. SENKO Advanced Components itself has 14 offices and dozens of design and manufacturing facilities providing local support to customers all around the globe. SENKO Advanced Components develops, manufactures, markets and distributes over 1000 fiber optic products for the telecom & datacom industries worldwide. SENKO Advanced Components was incorporated in the United States in the early nineties and has since being recognized as one of the industry’s specialists in passive fiber optics interconnect and optical components. An ISO-9001 approved company, SENKO is able to provide multinational corporations with the technical expertise to liaise with engineers, and the manufacturing flexibility to develop custom products for the ever growing high tech industry. Many of our products were created to resolve a specific design challenge faced by our customers. We offer one of the industry’s largest product portfolios, and our quality is second to none. Our mission is to be the best global provider of passive fiber optic components. We strive to provide an extensive portfolio of high quality products and services, available on a global scale, with excellent delivery time. We will stand by products, providing our customers with superior post-sales support. Our customers, suppliers and partners are essential to our success, and shall be treated with respect and integrity. Our team is committed to understanding the technical requirements and service expectations of our customers, and share the goal of resolving the specific challenges these clients face in their own business. 7 OPTICAL FIBER CONNECTOR HANDBOOK Basics of Optical Fiber Introduction to Optical Fiber The use and demand for optical fiber networks has experienced Wireless exponential grown over the past years. Optical fiber networks are widely deployed for various applications ranging from global telecommunications, signaling to desktop computers. These includes Telco/FTTx Data Centers the transmission of voice, data and video over short distances of meters to hundreds of kilometers across continents. Optical fiber is also used in systems for reliable and secure Silicon Photonics/ transmission of data and financial information between computer On-Board Optics terminals, companies and countries around the world. Cable television Security companies also use optical fiber to deliver data services and digital video content to consumers. With the introduction of online video streaming and higher definition video such as the 4K format and Medical Fiber Optic the upcoming 8K format, optical fiber is required to deliver higher bandwidth connectivity. Optical fiber also enables new technology, application and services such as remote learning and tele-medicine through transmission of digital content and low latency control of remote devices. Other applications for optical fiber includes automation, automotive, industrial, space and military. Optical Fiber Connectivity In order to build an optical fiber network, optical connectivity is required to extend, branch or split an optical fiber. There are mainly three methods to terminate an optical fiber, which are fusion splicing, mechanical splicing and optical connectors. Fusion splicing is the process of welding two optical fibers together. This is usually done by using and electrical arc in a fusion splicer. The ends of the two optical fibers are melted and forms a continuous bond. This method results in the lowest attenuation and reflectance. It also provides the strongest and most reliable joint between two fibers. Mechanical splicing is the process of jointing two optical fibers through a mechanical splice unit. The mechanical splice is a self-contained unit that has a V-groove which aligns the optical fiber within the unit. The two fibers are butted against each other with some index matching gel to improve the optical transmission. Mechanical splicing is a non-permanent connection. An optical connector is a termination at the end of an optical fiber that enables a quick and flexible fiber mating and demating compared to splicing. The connectors are mechanically coupled to align the fiber cores. Fiber optic connectors are usually used in situations that require quick fiber termination or increased flexibility such as in cross connection panels and customer premises termination. 8 OPTICAL FIBER CONNECTOR HANDBOOK Fiber Optic Connectors Basics of Fiber Optic Connectors There are many types of optical connectors. Different types of connectors are used depending on the equipment and application. Straight Sleeve Optical connectors have been designed throughout the years either for specific application, improving on existing connector quality or Ferrule Fiber to increase connection density. Optical connection are available for different types of fiber such as glass optical fiber, polymer optical fiber and plastic optical fiber. In addition, connectors are also available for both single mode and multimode networks. A good connector design is determined by factors such as low Alignment Sleeve coupling loss, interchangeability, ease of assembly, environmental resilience, high reliability, ease of connection, repeatability and low cost of manufacture and operation. There are many different types of connectors which use a variety of techniques for coupling such as bayonet, screw-on, latched and push/pull. Fiber optic connectors are mostly butt joint type connection where the optical fiber is secured in a precision alignment sleeve called a ferrule. Two connector ferrules are aligned and butted against each other within an adapter to complete the fiber optic connection. There are two commonly used butt-joint alignment designs which are the straight sleeve and tapered sleeve. 9 OPTICAL FIBER CONNECTOR HANDBOOK Fiber Optic Connector Assembly There are generally 3 steps in the optical fiber connector assembly which are adhesion, polishing and assembly. In this example, the general method of connectorizing an optical cord is outlined. STEP 1/3 AdHESION • The connector boot and crimp eyelet is slotted through the fiber cord • The cord is then stripped to expose the Kevlar and fiber buffer within the cord • The fiber buffer is then stripped to a certain measurement to expose the optical fiber and cleaned • A mixture of epoxy is prepared to be used as adhesive for the optical fiber in the ferrule • The connector ferrule is connected to a pump which sucks the epoxy into the connector ferrule • The prepared optical fiber is then inserted into the connector ferrule • The connector ferrule with the optical fiber is then placed in an oven for curing • After the connector ferrule is cured, excess fiber protruding out of the ferrule is carefully cut • The connector ferrule is now ready for polishing. boot, bare buffer crimp eyelet connector sub-assembly connector housing boot, short fiber ferrule dust cap 10 OPTICAL FIBER CONNECTOR HANDBOOK STEP 2/3 POLISHINg • The prepared connector ferrule is then affixed onto a ferrule holder jig • The jig is then secured onto a polishing machine above a polishing pad • Depending on the connector ferrule type and connector polishing requirements, suitable polishing films and polishing program are chosen • A piece of polishing film is placed onto the polishing pad.
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