Fiber optical networking –

July 12, 2013

What is Fiber Optic Splicing?

Knowledge of fiber optic splicingmethods is vital to any company or fiber optic technician involved in Telecommunications or LAN and networking projects.

Splicing is the practice of joining two fibers together without using fiber connectors. Two types of fiber splices exist: fusion splicing and mechanical splicing. Splicing may be made during installation or repair.

Splices generally have lower loss and better mechanical integrity than connectors, while connectors make system configuration much more flexible. So typically, splices are used to connect fiber cables in outdoor applications and connectors terminate fiber cables inside buildings.

Fusion splicing is to use high temperature heat generated by electric arc and fuse two glass fibers together (end to end with fiber core aligned precisely). The tips of two fibers are butted together and heated so they melt together. This is normally done with a fusion splicer, which mechanically aligns the two fiber ends, then applies a spark across the fiber tips to fuse them together.

Many telecom and CATV companies invest in fusion splicing for their long haul singlemode networks, but will still use mechanical splicing for shorter, local cable runs. Since analog video signals require minimal reflection for optimal performance, fusion splicing is more suitable for this application. The LAN industry has the choice of either method, as signal loss and reflection are minor concerns for most LAN applications.

The basic fusion splicing apparatus consists of two fixtures on which the fibers are mounted and two electrodes. Figure 1 shows a basic fusion-splicing apparatus. An fiber inspection microscope assists in the placement of the prepared fiber ends into a fusion-splicing apparatus. The fibers are placed into the apparatus, aligned, and then fused together. Initially, fusion splicing used nichrome wire as the heating element to melt or fuse fibers together. New fusion-splicing techniques have replaced the nichrome wire with carbon dioxide (CO2) lasers, electric arcs, or gas flames to heat the fiber ends, causing them to fuse together. The small size of the fusion splice and the development of automated fusion-splicing machines have made electric arc fusion (arc fusion) one of the most popular splicing techniques in commercial applications.

Figure 1- A basic fusion splicing apparatus

Fusion Splicing Method

As mentioned previously, fusion splicing is a junction of two or more optical fibers that have been permanently affixed by welding them together by an electronic arc.

Four basic steps to completing a proper fusion splice:

Step 1: Preparing the fiber – Remove the protective film, jackets, tubes, strength member, and so on. leaving only the bare fiber showing. The main concern here is cleanliness.

Step 2: Cleave the fiber – Using a good fiber cleaver here is essential to a successful fusion splice. The cleaved end must be mirror-smooth and perpendicular to the fiber axis to obtain a proper splice.

Note: The cleaver does not cut the fiber! It merely nicks the fiber and then pulls or flexes it to cause a clean break. The goal is to produce a cleaved end that is as perfectly perpendicular as possible. That is why a good cleaver for fusion splicing can often cost $1,000 to $3,000. These cleavers can consistently produce a cleave angle of 0.5 degree or less.

Step 3: Fuse the fiber – There are two steps within this step, alignment, and heating. Alignment can be manual or automatic depending on what equipment you have. The higher priced you use, the more accurate the alignment becomes. Once properly aligned fusion splicer unit and then use an electrical arc melting fiber, permanent welding the two fiber ends together.

Step 4: Protect the fiber – Protecting the fiber from bending and tensile forces will ensure the splice not break during normal handling. A typical fusion splicing have tensile strength between 0.5 and 0.5 pounds, and won’t break during normal processing, but it still needs to protect from excessive bending and drag force. Use heat shrinkable tube, silica gel, and/or mechanical crimping protector will remain joint protection from external elements and breakage.

In general, fusion splicing takes a longer time to complete than mechanical splicing. Also, yields are typically lower making the total time per successful splice much longer for fusion splicing. Both the yield and splice time are determined to a large degree by the expertise of the fusion splice operator. Fusion splice operators must be highly trained to consistently make low-loss reliable fusion splices. For these reasons the fusion splice is not recommended for use in Navy shipboard applications.

July 1, 2013

AFL Offers Fujikura 70R Ribbon Fusion Splicer to North America

AFL has launched sales of the Fujikura 70R fusion splicer in North America, which is following the 12s, 12R, and 70S models. This product is recorded to the be the fastest ribbon fusion splicer in the world until now. The new design streamlines the steps required to complete splices, resulting in greater productivity, which is based on the success of the Fujikura 60R ribbon fusion splicer.
“The 70R builds on the excellent track record set by the 60R. With the automated wind protector and tube heater, quality splicing is even faster. The tube heater clamps the splice protection sleeve from both sides, resulting in a shrink time of an impressive 40 seconds. ” Commented Greg Pickeral, product manager, fusion splicing systems for AFL.

Enhanced features of the Fujikura 70R fusion splicer include:
Automatic and fully programmable wind protector
40-second tube heater
Electrodes with enough life to support 1500 splices
High capacity Lithium-Ion battery pack (110 splices/shrinks)
On-board training and support videos
A six-direction drop-proof design with fully ruggedized rubber casing
Dust- and rain-proof exterior
A transit case with a detachable, built-in worktable
Full compatibility with the FuseConnect line of splice-on fiber-optic connectors
The 70R is one of several new splicer introductions from Fujikura this year. Later this year, Fujikura plans to unveil the 19s, a fixed V-groove single-fiber fusion splicer, and 19R four fiber ribbon fusion splicer.
Kindly note that the Fujikura ribbon fusion splicer 60R, 60S, 80S, and more fusion splicers are all available at FiberStore. Click and get a big surprise for the price!

May 2, 2013

When Do We Need Fiber Optic Splicing

When we want two fibers or fiber optic cables joint together, there are two method come to our head, installing a fiber optic connectors at the end of the optical fibers, or splicing the two optical fibers. Fiber optic cable splicing is a method that creates a permanent joint for two fibers, while fiber connector installation is used for temporary connections. There are two options for fiber optic splicing: Fiber optic cable fusion splicing and mechanical splicing. Both methods provide much lower insert loss than fiber optic connectors.

Common application for splicing is jointing cables in long outside plant cable runs where the length of the run requires more than one cable. Splicing is generally used to terminate singlemode fibers by splicing preterminated pigtails onto each fiber. It can be also used to mix numbers of different types of fiber cables like connecting a 48 fiber cables to six 8 fiber cables going to different places.

Fusion splicing provides a maximum insertion loss of 0.1 which is less than 0.5dB of mechanical splicing. Fusion splicer are available in two types that splice a single fiber or a ribbon of 12 fibers at one time. Almost all singlemode splices are fusion spliced. Mechanical splicing is most used for temporary restoration and for multimode splicing. Fusion splices are so good today that splice points may not be detectable in OTDR traces.

Fusion Splicing Process
Fusion splices are made by welding two fibers together by an electric arc of the fusion splicing machine. It can be not done in the enclosed space for safety reasons. It is suggested to done the job above the ground in a truck or trailer for a clean environment for splicing.

Fusion splicing needs the help of a special equipments which is fusion splicer to perform the splicing process. Main steps are aligning the two fibers precisely and generate a small electric arc to melt the fibers and weld them together.Splicing machine can do one fiber at a time while mass fusion splicer can do all 12 fibers in a ribbon at once.

Preparing fibers: The first step for fusion splicing is to strip, clean & cleave the fibers to be spliced. Stripping the primary buffer coating to expose the proper length of bare fiber with the fiber stripper. Clean the fiber with appropriate wipes, what you need is the fiber optic cleaning kit, Cleave the fiber using the directions appropriate to the fiber cleaver being used. Place each fiber into the guides in the fusion splicing machine and clamp it in place.

Running the splicer program: Choose the proper program according to the fiber type being spliced. The splicer would show the fibers being spliced on a video screen. The fiber ends will be inspected for proper cleavers and bad ones will be rejected for a second time cleaving. The fibers will be moved into position, prefused to remove any dirt on the fiber ends and preheat the fibers for splicing. The fibers will be aligned using the core alignment method used on that splicer. Then the fibers will be fused by an automatic arc cycle that heats them in an electric arc and feeds the
fibers together at a controlled rate.

Ribbon fusion splicing: Each ribbon is stripped, cleaved and spliced as a unit. Special tools are needed to strip the fiber ribbon, usually heating it first, then cleave all fibers at once. Many tools place the ribbon in a carrier that supports and aligns it through stripping, cleaving and splicing. Consult both cable and splicer manufacturers to ensure you have the proper directions.

Fusion splicing pigtail is another typical application for fiber optic splicing. By this method, a fiber optic patch cord is cut into two pigtails with connectors attached. The fibers are cleaved and welded together with a fusion splicer, which is considered to be the fastest and highest-quality method of fiber connector installation.

April 23, 2013

General Fiber Splicing Technology

Category: Fiber Optic Splicing – Tags: , , – ingellen 7:08 am

Fiber splicing involves joining two fiber optic cables together to establish an optical connection between two individual optical fibers. Fiber optic splicing typically results in lower light loss and back reflection than termination.

Fujikura FSM-60R Mass Fiber Fusion Splicer

Splicing is needed if the cable runs too long for one straight pull or you need to mix a number of different types of cables (like bringing a 48 fiber cable in and splicing it to six 8 fiber cables). And of course, we use splices to repair damaged optical fibers during installation, accident, or stress. After the number one problem of outside plant cables, a dig-up and cut of a buried cable, usually referred to as “backhoe fade” for obvious reasons. System design may require that fiber connections have specific optical properties (low loss) that are met only by fiber-splicing. System designers generally require fiber splicing whenever repeated connection or disconnection is unnecessary or unwanted.

Fusion Splicing & Mechanical Splicing
Splices are “permanent” connections between two fibers. There are two common methods used to join optical fiber cables –Fusion Splicing & Mechanical Splicing, and the choice is usually based on cost or location. Most splicing is on long haul outside plant SM cables, not multimode LANs, so if you do outside plant SM jobs, you will want to learn how to fusion splice. If you do mostly MM LANs, you may never see a splice.

Fusion splicing is the act of joining two optical fibers end-to-end using heat. The goal is to fuse the two fibers together in such a way that light passing through the fibers is not scattered or reflected back by the splice, and so that the splice and the region surrounding it are almost as strong as the virgin fiber itself.

The principle of fusion splicing is that the two bare fiber ends (with coatings removed) are fused together under the influence of heat. More precisely, the fiber ends are initially brought in close contact, with a small gap in between. After heating them for a short while such that the surfaces melt, they are pushed together, such that the ends fuse together. In fusion splicing, splice loss is a direct function of the angles and quality of the two fiber-end faces. When doing fusion fiber optic splicing, usually people need Heat Shrink Tube splice protect sleeves to protect the fiber splices after the work is done.

Mechanical Splicing is a fiber splice where mechanical fixtures and materials perform fiber alignment and connection. Mechanical splicing is an optical junction where the fibers are precisely aligned and held in place by a self-contained assembly, not a permanent bond. This method aligns the two fiber ends to a common centerline, aligning their cores so the light can pass from one fiber to another. Mechanical fiber optic splicing is used for a quick repair and when only a small number of splices are required, its average cost for a single fiber optic splicing is high.

As for the performance of each splicing method, the decision is often based on what industry you are working in. Fusion splicing produces lower loss and less back reflection than mechanical splicing. Fusion splices are used primarily with single mode fiber where as Mechanical splices work with both single and multi mode fiber. The equipment to perform fusion splicing, named fusion splicer, is commercially available with a wide range of models.

April 1, 2013

Fiber Testers Of Fusion Splicer

Category: Fiber Optic Splicing – Tags: , – ingellen 4:54 am

fusion splicer is a device that uses source of heat to melt two optical fibers together at their end faces, to form a single long fiber. The resulting joint, or fusion splice, permanently joins the two optical fibers end to end, so that optical light signals can pass from one fiber into the other with very little loss. The source of heat is usually an electric arc, but can also be a laser, or a gas flame, or a tungsten filament through which current is passed.

Features of Fusion Splicers:
Carefully engineered fiber clamps allow the precise fixing of the fiber ends. At least one clamp is precisely adjustable with micrometer screws;
For splicing polarization-maintaining fibers, it is also necessary to rotate one of the fibers around its axis;
A microscope allows inspection of quality and alignment of the fiber ends. Often, there is a knob for switching between two orthogonal directions of view. The fiber cores can also usually be seen;
A “prefuse”, applied without touching the fibers, allows one to clean the surfaces;
Some splicers do the alignment automatically based on a camera image and/or on monitoring the optical power throughput. For the latter, there must be a light source attached to one fiber end, and a photodetector for the other one;
Some devices can also measure the quality of the resulting splice.

The process of Fusion Splicing involves using localized heat to melt or fuse the ends of two optical fibers together. The Splicing process begins by preparing each Fiber end for fusion. Fusion splicing requires that all protective coatings be removed from the ends of each fiber. The fiber is then cleaved using the score-and-break method. The quality of each fiber end is inspected using a microscope. In fusion splicing, Splice Loss is a direct function of the angles and quality of the two fiber-end faces.

Before optical fibers can be successfully fusion-spliced, they need to be carefully stripped of their outer jackets and polymer coating, thoroughly cleaned, and then precisely cleaved to form smooth, perpendicular end faces. Once all of this has been completed, each fiber is placed into a holder in the splicer’s enclosure.

Cleaning the splicing device and the fiber
Since the slightest trace of dust or other impurities can wreak havoc on a splice’s ability to transmit optical signals, you can never be too clean when it comes to fusion splicing. Even though fibers are hand-cleaned before being inserted into the splicing device, many fusion splicers incorporate an extra precautionary cleaning step into the process: prior to fusing, they generate a small spark between the fiber ends to burn off any remaining dust or moisture.

The fiber is then cleaved using the score-and-break method so that its endface is perfectly flat and perpendicular to the axis of the fiber. The quality of each fiber end is inspected using a microscope. In fusion splicing, splice loss is a direct function of the angles and quality of the two fiber-end faces. The closer to 90 degrees the cleave angle is the lower optical loss the splice will yield.

Splicing Optic Fiber
The splicer emits a second, larger spark that melts the optical fiber end faces without causing the fibers’ cladding and molten glass core to run together. The melted fiber tips are then joined together, forming the final fusion splice. Estimated splice-loss tests are then performed, with most fiber fusion splices showing a typical optical loss of 0.1 dB or less.

Fiberstore is the recognized leader in the development of the highest quality fusion splicing equipment and accessories that have and continue to advance fusion splicing technology. You have a wide selection of fiber optic splicing relevant equipments, like fusion splicer, fiber optic cleaver, fiber cleaver blades, fusion splicer assemblies, etc.