Fiber Optic Fusion Splicers
Fusion splicers create strong and reliable connections between fiber optic cables, helping ensure that networks can continue to transmit data. This reduces the risk of cable breakage and signal interruptions, allowing companies to minimize maintenance costs and downtime.
Calibrated fusion splicers accurately align the fibers, minimizing reflections that can cause insertion loss and reduce data transmission efficiency. This allows for faster, more reliable connectivity, which is essential in today’s digital world.
Core Alignment
The key to a flawless fiber splice is achieving impeccable core alignment. Perfect core alignment ensures that the transmission and receiving ends of optical fiber match up perfectly, resulting in zero signal loss and fiber-optic-fusion-splicers exceptional network performance. To achieve this, service providers need to take several key steps, including implementing the right splicer technology, conducting proper preparation of the optical fiber, focusing on precise cleaving and ensuring regular calibration and verification of the splicer.
The two main types of splicers used in the field are V-Groove and Active Cladding Alignment (ACAL). The V-Groove splicers use passive alignment that utilizes V-grooves on both sides of the splicer to align the fiber’s cladding, or outer surface. The ACAL splicers use image and light detection systems to ‘see’ the fiber’s cores and automatically adjust the core-to-core positioning. This more accurate alignment allows for a better splice performance as it compensates for influences like contamination on the fibre’s cladding, core-cladding eccentricity and mode field diameter (MFD) mismatches.
The ability to align the cores is also important for Single-Mode Fiber to the Home (FTTH) networks. One of the most common causes of splice loss in FTTH is end separation, which occurs when the transmitting and receiving ends of optical fibers separate. This can cause multiple types of losses, such as Fresno reflection and insertion loss. IPA2’s new LMA core alignment technique is able to accurately align octagonal active and round passive LMA fibers by finding the center of a bright region of the brightness intensity profile, which shows the core brightness peak.
Pre-Fuse
Optical fibers must be stripped, cleaned and cleaved to prepare them for fusion splicing. The process of exposing the ends of the fibers to a high-voltage electric arc heats and melts them together, producing a permanent connection. Ideally, splices are as seamless and attenuation-free as possible. Splicing eliminates the need for connectors, reducing signal loss and providing a more reliable network.
To achieve this, the splicer must identify each end of the optical fiber and align them properly. This is typically done by using a video camera, optical power meter or a viewing scope. The splicer will typically reject badly cleaved or aligned fiber ends, and some will automatically clean the fiber ends prior to the splicing cycle.
Ultimately, the decision of whether to use fusion or mechanical splicing depends on the type and scale of the network. While mechanical splices are easier to install and work well in most environments, fusion splicing provides a more durable connection that is less prone to damage from environmental factors. As a result, it is better suited for long-haul outside plant (OSP) applications and some premises LANs. It is also the preferred method for FTTH installations, as it provides lower splice losses than other termination methods. In addition, a fusion splice can be quickly repaired by adding a new splice to the broken fibers.
Splicing
A splicer can either conduct one fusion splice at a time (single fiber models) or multiple splices of a ribbon cable at the same time (ribbon fiber models). Splicers may use an image or monitoring system to align the fiber ends before they are fused together. Some devices also offer a “prefuse” feature that allows users to clean the surfaces of the spliced fiber ends before they are fused. Splicers can splice single- or multi-core optical fiber, polarization-maintaining or non-polarization-maintaining. Splicers also come in a variety of sizes and styles. For example, a ribbon fiber splicer can handle up to 16 fibers at once and may include a heating device for securing the splice with a heat-shrink sleeve.
Before splicing, the fiber optic cable must be cleaved using an appropriate cleaver that produces a precise break with end faces that are flat and perpendicular to the core axis. Using a cleaver that doesn’t produce a precise break can result in high attenuation loss, even with careful alignment of the spliced ends between the electrodes of the fusion splicer. In addition, contamination from the cleaver or optical fiber that is invisible to the naked eye can still cause attenuation loss. Always ensure that you’re using the correct cleaning products and processes recommended by both the cleaver manufacturer and fusion splicer manufacturer.
Post-Fusion
A fusion splice is permanent and can’t be removed like a connector. Therefore, the splice must be protected from bending and tensile forces, which could cause it to break. The best way to do this is to wrap the splice area with heat shrink tubing, which will protect it from environmental conditions as well as mechanical stress.
Fusion splices are not as good at transmitting data as a connector, but they do have a much higher level of mechanical strength. Splice points can withstand a lot more than a connector, but fiber optic components they still require care in the field to avoid contamination, which will increase the loss of the system. It is important to use the appropriate cleaning products and cleaning process specified by both the splicer and cleaver manufacturer, as well as making sure the cleave length and angle are correct for each unit.
A splice point must also be protected from dust and dirt, which can increase insertion loss and back reflection. This is typically done by wrapping the entire splice area with a protective sleeve, which can be heated in an electric oven built into the fusion splicer to shrink around the fiber core. This can be particularly critical on FTTH networks, where splice points are frequently located near power lines and other conductive objects.