Fiber optic splitters enable a signal on an optical fiber to be split between two or more fibers. Since splitters do not contain any electronics and do not require power, they are integral components and are widely used in most fiber optic networks. As a basic example, the following diagram shows how the light in a single input fiber is divided among four separate fibers (1x4):
Splitters can be constructed using a variety of singlemode and multimode fibers and most connector types for a variety of applications.
From a technical point of view, there are two commonly used types of splitters:
1. FBT splitter
2. PLC splitter
plc splitter
As with most technologies, each type has its advantages and disadvantages when deploying them in passive optical networks.
FBT is a traditional technique in which two fibers are placed close together and fused together by heat as the component elongates and tapers. The signal source is used to determine the point at which the desired coupling ratio is met, and then the process is stopped.
As this technology continues to evolve, FBT splitters are of very good quality and can be deployed in a cost-effective manner. FBT splitters are widely accepted and used in passive networks, especially in smaller split configurations (1x2, 1x4, etc.).
The disadvantage of this technique occurs when larger split configurations (1x16, 1x32, 1x64, etc.) are required. FBT technology can achieve a limited number of mass splits in a single instance, so when larger split configurations are required, multiple must be stitched together. As a result, the physical size is increased due to the multiple splitters, and the additional losses of the splice are also increased. Therefore, for these cases, as we will discuss in the next section, a PLC splitter is more ideal.
Planar Lightwave Circuit Splitter
PLC splitters are a newer technology and offer a better solution for applications requiring larger split configurations. To achieve this, photolithographic techniques are used to fabricate waveguides onto a quartz glass substrate, allowing a specific percentage of light to be routed. Thus, PLC splitters can provide very accurate and even uniform separation with minimal losses in a very efficient package.
With the rapid growth of global FTTx, the need for larger split configurations (1x32, 1x64, etc.) in these networks is also growing to serve large numbers of subscribers. PLC splitters are now an ideal solution for this type of application due to the performance benefits and overall low cost of deployment.
