Two Common Types of Optical Splitters –FBT And PLC

Over the past few years, optical technology has made a huge step forward to meet the growing demands for optical performances in fiber applications. Take splitter technology for example, advances have been made in its fabrication and packaging, which makes optical splitters an even more important passive device in passive optical networks (PON) .

Optical Splitter

Optical splitter, known as a beam splitter, is based on a quartz substrate of an integrated waveguide optical power distribution device, similar to a coaxial cable transmission system. As an important component in passive optical networks, optical splitter is also called passive optical splitter or PON splitter, which is used to split the fiber optic light evenly into several parts at a certain ratio. Optical splitters are manufactured commonly in two types according to working principle—FBT (Fused Biconical Taper) splitter and PLC (Planar Lightwave Circuit) splitter. Each type has its own performances.

FBT Splitter

Fused Biconical Taper is a kind of traditional technology in which two or more than two fibers are welded closely together by applying heat. There are ample materials available used for making FBT splitters, such as the steel, fiber, hot dorm. They come at a low price, which explains the cost-effective feature of the device itself. As this technology has been developed over time, FBT splitters are more and more qualified for various application. They are applicable for both single-mode and multi-mode fibers compliant with a variety of connector types, widely accepted and used in passive networks, especially for instances where the split configuration is smaller (1x2, 1X4, 2x2, etc.). The following picture shows a 1x4 single-mode FBT splitter.

However, FBT splitters only support three wavelengths (850/1310/1550 nm), meaning that they are unable to operate on other wavelengths. Moreover, they are demanding for a stable working range of -5 to 75 ℃, sensitive to a high extent temperature. For FBT splitters, the very precise evenness in splitting signals is impossible due to lack of management of the signals.

PLC Splitter

Planar Lightwave Circuit splitters, which base on the more recent Planar Lightwave Circuit technology, offer a better solution for applications where larger split configurations are required. They support wavelengths from 1260 to 1650 nm, a wide range appropriate for wavelength adjudication. Besides, the temperature range (-40 to 85 ℃)is workable for PLC splitters, allowing for their utilization in extreme climate. In addition, the signals can be split equally due to technology implemented. The drawback comes that PLC splitters are fabricated by using semiconductor technology (lithography, etching, developer technology) production, so it is more difficult and complex to manufacture them. Consequently, the price of PLC splitter itself is higher. A figure of a 1x4 Fiber PLC Splitter with Plastic ABS Box Package is below.

Both FBT splitters and PLC splitters have found their ways in passive optical networks with the rapid growth in FTTX networks. In Fiberstore, you can find PLC splitters with standard LGX and ABS box package, as well as FBT coupler splitter with single, dual and three windows for PON system.